What limits you as a genealogist? How do your perceptions of, and expectations for, your research contrast with what you can actually accomplish? These are uncomfortable questions. But I believe that they're important ones to confront for maximizing one's potential. Producing solid work takes time, effort, skill, growth, and resources. Here are some of the major impediments.
1. Cannot locate or access needed sources.
This one inevitably hangs us all up at some point. Every ancestral line going back ends with a question mark. Even the best researchers eventually run out of records, or they have no way of knowing what clue may reside in an obscure source at some unknown location. You can also have all of the experience in the world, know where needed records are, and still be unable to access them due to unforthcoming archivists, steep travel expenses, or other barriers beyond your immediate control.
While everyone deals with these problems to some extent, beginners don't know how to deal with them. They may know about certain primary source records, but do not think it necessary to consult them. They may not even understand that they're crucial. They say things like, "well, I'm happy with the number/kinds of sources I have for this person or fact." Or, "I've found all I need on the internet." This is pure dilettantism, and it makes an already serious problem (access) for any genealogist that much more limiting.
2. Cannot read/interpret primary sources.
From what I have seen, this can be a serious stumbling block. I'm not just talking about one's inability to read or understand needed primary sources; I'm talking about the failure to understand why these skills are important. I often bring this issue up with the I-Can-Trace-Back-To-X-Medieval-King people. I'll ask them which primary sources they have seen, and whether they can read anything that's not in modern English. If I ask this on a social media forum like facebook, the indignant responses I receive can make it appear as if I just canceled Christmas. If the original poster/commenter is honest, they'll often admit that they don't have good evidence linking them to much more recent ancestors in their "royal" lines, much less evidence sufficient to span enormous quantities of years and support cross-epochal connections.
You may be one of those who hates questions like these, but that doesn't change the unpleasant realities they expose. If you're relying upon secondary sources (in the worst cases a Wikipedia article or somebody's dubiously sourced tree online), you're relying upon someone else's work. As James Tanner has said, copying other people's research is not doing your own research. Most of us are best qualified to study primary sources pertaining to relatively recent ancestors. The number of people who do genealogy at all is much greater than the number of people who possess the expertise required to use sources that aren't in their mother tongue, or that come in forms beyond simple vital or other typical records. How do you become a person who can do more than this? Education and practice. (See point #8.) Professional historians work decades to perfect the skills necessary to find, read, and properly interpret needed primary sources in different languages and/or from remote times.
3. Refusal to cite sources, or citing them only inadequately.
The oft-stated maxim "genealogy without sources is mythology" is absolutely true. And you can tell this to gleeful amateurs who will resolutely refuse to heed it. Jesus said that the poor with always be with us; the same is true for the throngs of people who simply refuse to cite sources for the information they add to their trees. Unfortunately, many never get past this stage.
Then, there are some people who understand that they need to cite sources, but they provide citations of the most rudimentary kind. This applies to many who contribute to Big Collaborative Trees online. You'll often see something like "1900 U.S. Census" or "Death Certificate of Deceased" listed as a citation, with no other information given. But listing the repository, date accessed, and other information in citations is actually an important part of the research process. The "when," "where," and "how" matter, and not just the "what" (or part of the "what"). As the researcher becomes more experienced, he/she begins to be mindful of an increasing number of details and nuances, and how important they are for confronting difficult problems. Learning how to craft full citations is an essential step in this process, and achieving it signals a major step forward for the genealogist.
4. Exercising too much wishful thinking, and too little restraint and skepticism.
If you want to be related to royalty badly enough at the outset, you'll probably find a way to "make it happen." If you like the barely plausible story that your Aunt Mabel tells you about a family member, you'll record and present it as fact without much afterthought. If you are initially unsure about who is in an old photograph, and you want it to be your elusive great great grandma badly enough, you'll put her name on the back of it and pretend that's the end of the matter. If you want a particular possibility suggested by your source to be true, you'll treat it as historical fact and ignore evidence for opposite conclusions.
Need I keep going? We've all had temptations like these. When we were first starting out, we may have routinely yielded to some of them. But if you never get past these tendencies, you're severely limiting yourself as a genealogist. Good researchers know that lingering questions and uncertainties are the name of the game. And while they mean that we may have to take more notes, wait years for solutions that many never come, and have less glitzy stories with which to impress others, the responsible thing to do is to admit when something is an unsolved mystery or goes against how we want to see ourselves and our ancestors.
5. Poor organization.
Limited researchers not only don't know how to use what they have; they often forget what they have or where it is. Or, they can't use what they have as effectively as they might. As I said in a recent post, mature researchers are also part-time archivists. They keep detailed lists of their records, and what they have and don't have. They maintain easily accessible databases where they can quickly locate desired items. They are in firm command of their tools and resources. They have clear goals for their research, and can effectively trace their progress. As the genealogist becomes more experienced, the scaffolding becomes nearly as important as the building. Indeed, it often happens that the latter is weakened by a lack of the former. If you have yet to become well organized as a genealogist, you should start taking this aspect of the pursuit seriously. Drew Smith's book Organize Your Genealogy: Strategies and Solutions for Every Researcher (Family Tree Books, 2016) is an excellent guide.
6. Poor note-taking habits.
This goes back to the wonderful article on the FamilySearch Wiki about Rookie Mistakes. I have little to add here, except to repeat that research logs and notes sharpen the genealogist's work. They help him/her solve knotty problems and avoid duplication of efforts. They track progress. They aid good organization. Perhaps most importantly, they allow other researchers to effectively carry on one's work after one is gone.
This relates closely to Factor No. 4. I've said this before in my blog posts: little about genealogy done well is quick or easy. Quality work takes TIME. Tracking down needed sources requires the same. I often wait months and YEARS to make trips to the places where long-anticipated records reside. I often spend hours adding just one person to my main tree, formatting all of the citations for their relevant sources, making sure those sources are attached to the right facts and other names, and making notes about what's missing/uncertain/etc. And that's just the initial pass. Citations, notes, and facts must occasionally be tweaked and refined ever after. If you're doing any of this willy-nilly, you're doing it wrong. Treat adding anything to your tree as the significant task it is.
8. Not putting in the time and effort to improve.
People who do genealogy (or what in their minds passes for genealogy) purely for entertainment stand little chance of real progress. But if you're in this pursuit to create something of lasting value, you'll continually educate yourself and strive to improve as aware and needed. This includes reading books/articles/blogs, watching educational videos, attending local conferences and society meetings, and (perhaps above all) learning and practicing new skills and knowledge sets. We all have different talents and capacities for historical research, but one doesn't need to be the greatest researcher in the world to make a difference in effectively documenting one's family history. On the other hand, ignoring constructive advice, and/or persisting in bad habits because they're comfortable, is a sure way to go nowhere, and even (at times) to spread misinformation. Which finally leads to:
9. Lacking humility.
In my experience, it's not the expert who most often lacks humility in the greater genealogical community, it's the obstinate amateur who bristles at well-meant advice. The bigger problem is not the seasoned researcher whose "killjoy" skepticism annoys newcomers, but rather it's the bellicose tale-spinner who, out of pride or a sense of self-superiority, makes loud assertions about their highborn or otherwise glamorous roots, will suffer no scrutiny or gainsaying, and will negatively influence impressionable people who might otherwise be taught good habits. I ask you again: why do you do genealogy? If it's to pursue the truth about where you came from and who went before you, then a healthy dose of humility is a dear companion on the road to doing so. The more you discover, the more you realize that most of your ancestors lived quite modest lives, and that boasting of any royal connection (real or, more likely, imagined) means little. In the words of the great Donald Lines Jacobus, "for every one descent I might claim from King Alfred, I could claim a million from the peasants of his time, if records had been kept of the lower classes" (from Genealogy as Pastime and Profession, Second Edition, pg. 35). But whatever your actual background, success in any historical research involves recognizing what you don't know, and never being too proud to accept the instruction and correction of others.