Long time (18 month lurker on TRP). I'm constantly on and off monk mode, working on interests, fixing my shit, lifting, meditating, etc.
What brings me OFF monk mode is that I no longer have any fun, all the things I do I do for improvement's sake, there is nothing I find ot be enjoyable. I like being good at things, but I feel no happiness from much of anything.

I love being good at tennis, I practice hard. I like putting up numbers at the gym, I lift hard. I like musing, I introspect and read.
I'm having no fun though, no time when I'm performing an activity simply for the joy I get from doing it.
It's making monk mode hardly sustainable because all I'm ever thinking about is improvement. It's frankly driving me crazy. What do you do to just let go and enjoy things?