I am also wine maker and in need of one analytical tool and found out that it costs 30k, amount I can't afford (or even justify for business my size) so I found a way to create same tool that will costs just 3k.
First category is kind of simple: I do need it and the app is simple enough I can do it in few evenings so I just do it. The second category is something I really need and will be really happy if somebody else created it and because there is nothing like that on the market I have to do it by myself (and then sell it to other winemakers who I am sure need it as well).
The problem for me is the middle ground: something I found quite interesting (say nicely formatted tabs app with timing, sounds, fretboards...) and might use it from time to time. But the novelty wears off soon and I am not desperate to have it in my life. Still these kinds of projects need sustainable effort to make it work so I just keep working less and less on it and then quit.