Epiphany.
You're deathmarching out the final stages of a project, you're sacrificing your mind and body and sanity. You're burning midnight oil, both ends of the candle, your family and friends haven't seen you in a while.
You're wrecked. Can you get it done? So close, so close... strength is failing, can we get over the line?
And - you do!
You get it done!
Bam! Euphoria!
But then - now what?
Nothing?
....damn it...
Motivation is sunk after that, and you fall into a funk.
If you've followed my writing for a while, you know I'm not big into celebrations and festivals. I don't celebrate any of them, not even my own birthday.
I've always discounted festivals as not very important if you live a high impact and reflective life all the time anyways.
But! If there's any use for them, it's to prevent the anticlimax after a huge effort.
It's like, if that's it and you now have to sit around and wait, you're hosed.
But if there's a party scheduled in, say, two weeks, you can take it easy for a few days, then catch up on all the maintenance that's been piling up, knowing all the while that you're having a party marking your new launch.
If you're managing, even just a short, "Congrats! I'm super pumped for this" or something probably goes a long way.
I'm not sure exactly what the right answer is if you're doing things solo, but anticlimax is clearly a big killer. Plan some sort of transitional celebratory event around the end of any huge effort push so you don't fall apart afterwards.