The important lesson I have derived is that whenever someone undertakes a project management task, they often lack clarity about their requirements at an early stage. When the requirements are not clear, they tend to change, leading to scope creep. As a result, any estimates you have made are likely to be altered. Therefore, I would suggest that when making project estimates, one should include a margin of error to account for potential overshooting and determine a comfortable level to restrict the extent of scope creep. Otherwise, it becomes difficult to understand what project is being undertaken and what the actual requirements are. It's only during the development phase that the true nature of the project becomes apparent.