It’s all very well to have good ideas on the drawing board, in practice they might not work. History is littered with great theories and good intentions which ended up backfiring horribly.
Chess is like that too. We might have the idea to learn a really ‘good’ defence against 1.e4, such as the Sicilian Najdorf, only to find that the learning and upkeep required is simply impractical.
How should we combat this tendency? Essentially by listening carefully to the feedback we get from implementing our ideas in practice. Are they working as expected? What were the problems and/or concerns that arose? Making notes can be very useful in this regard, for example by keeping a tournament diary.
Experience has taught me to be very wary about making big chess improvement plans, preferring instead to feel my way and listen carefully to the feedback I’m getting. There have been times where I kept a tournament diary, and the learning experience proved to be invaluable.
One thing that kept coming up was basic opening preparation, having a game plan against the various things my opponents could throw at me. The answers didn’t need to be the best and sharpest available, it was simply a question of getting a playable middle game position.
Did I go home and do the necessary repairs? Sometimes, but not always. And the problem was in getting distracted by some more grand plans.