There's no way to know for certain because the developer gets too defensive about it to ever really examine it for himself - but everyone's got their theories.
My theory:
There's an expression 'A goldfish will get as big as the bowl if you let it' - literally meaning that a goldfish can just keep getting bigger/fatter if you keep feeding it just a little too much every day.
At some point in 2018 L&P got to a development speed where it was taking him 6 months for a single, Whole-Day update - for multiple updates in a row.
His fans complained about the long wait between new content - which he interpreted as fans wanting more of the game, even if the trade-off for that speed is a smaller update with fewer scenes. So he moved to Half-Day updates.
But - now we get to the Goldfish analogy - after a while putting out Half-Day updates at a faster rate, L&P started to reason that he can expand the content a little... since he's got the time.
"There's so few scenes in this update, maybe I'll just fill out this scene with a few extra renders, just a handful. Oh but now the next scene is so short in comparison I should pad it out with a few extra renders as well. Oh but now I look at it - I should throw out and re-do the renders for this whole sequence because the lighting doesn't look quite right, I've got the time after-all it's only a Half-Day update."
That's how we ended up with Half-Day updates that took ~6 months to make.
Then... wouldn't you know it, his fans complained about the long wait. He interpreted this as fans wanting more of the game, again at a trade-off of smaller updates, so he moved to One-Third-Day updates.
And the cycle repeated itself.
There are early game days with around 500 renders total.
The current game day will finish somewhere just shy of 3000 renders.
There are lots of people here and elsewhere on the Internet that are unhappy with this and voice their complaints every chance they get - but their voices will never carry the same weight as his paying Patrons (understandably so), and the paying Patrons love the bigger updates and praise him for his huge, massive, girthy... render count. Think of them as the ones sprinkling goldfish food into the bowl.
He has paying Patrons who complain about update bloat and want him to work faster, I was one of them, but those complaints are isolated voices, drowned out by the other more positive supporters. Paying Patrons who complain and see that their complaints are ignored eventually stop paying, meaning L&P's Patrons are always going to be majority in support of his slower work.
So he keeps taking steps to put the game out 'Faster' - that actually result in the ending of the game getting further and further away.
At some point in the future (to be honest I think it'll be soon) he'll announce that he's moving to Quarter-Day Updates.
Then a year or two after that he'll announce that Quarter-Day updates are taking too long and he's switching to Single-Event Updates.
Then, a year or two after that, when his Patrons are waiting 6 months for a Single-Event Update that contains 800 renders - I'm hoping that will be the final straw and even his most loyal paying Patrons will speak up about wanting him to make real changes to his development process.
