It is so important to spend the time to do the proper research, document your findings, transcribe your documents, and extract the important facts and relationships that help build a reliable family tree. The genealogy research process in not for the faint of heart. It is a 28 step process, if done right. This is done over and over again for each person, and each fact that is recorded in a family tree.
All too often people say they have 4,000 people in their tree. The mythical story of Alice in Wonderland surely had genealogy in mind when that story was written, as millions of people follow the same rabbit hole as pointed out in the article written by "They Came Before". Too many people have little to no sources to back up the information they record in their family tree, and they don't understand evidence, sources, and proof. To top that off, the information recorded all too often comes from trees that they found on the internet and have not bothered to verify the data, or if they did, they used only one or two census records. Evidence cannot be gleaned with a single source, or a single source type.
Documenting your sources, where you received the information, how the data is related to your relatives and how you developed those conclusions is a daunting task in itself. Then keeping all the data organized is important too. It is not just about putting the data into a tree, or folders. It is also about being able to understand and decipher what facts and relationships still need to be verified and do you have enough to proof to say your ancestor belongs in your tree? Have you found enough evidence that the recorded facts are true? A good article to read is "Appraise Your family History Like an Archivist".
Developing good genealogy research habits and processes go a long way with being successful in building a reliable family tree. Don't forget about organization and documentation too. What have you done to enhance your family tree lately?