Endless Projects Must Be Limited
There are only so many hours in the day. If you have a task/skill that requires regular practice, say, an hour a day, then you cannot have more than say, 8 total things that need to be tended to for an hour a day (and this is a very high estimate, assuming you don't do things like cook, clean, take care of kids, commute, shower, etc...). At a certain point, you have to say "these are the things I can commit to doing regularly, and everything else will have to be let go." Some people deal with this by hyperfocusing for a few months on some particular area, then pulling back, but that seems like it won't lead to long-term success or skill improvement ("Oh, I'll just practice piano really intensely for three months, then never again"???).