I've noticed that with a few projects. One infamous example that comes to mind immediately are the works by Kyle Mercury or Siren. They're basically at the mercy of their artists. The latter of which had to switch art styles 3 times.
I can't even come up with a viable solution other than locking down an artist on retainer/exclusively, but that's obviously going to be far more expensive.
It definitely would be very expensive, because in order to have a faster pace of artwork, you'd have to be able to pay an artist enough for them to be able to survive off of it while they take no commissions/additional work. And even then, drawn artwork still takes considerable time when it's higher quality.
We were able to have Soapmonster work almost exclusively on Insexual Awakening artwork, but it quickly became difficult with Erolon.
For many artists, (especially those in expensive cost of living countries like the USA) it's nearly impossible to work on one game for minimal pay.
As a matter of fact, for Erolon all of the income from patreon has exclusively gone to paying artwork for the past 6-8 months, and DrX and myself have not received any income from it. So all the programming DrX does and all the writing I do is being done for no pay at this point.
This isn't a complaint, it's just pointing out how much the slow art cycle has contributed to the vicious cycle of losing support.
This is one of the big reasons why DrX and myself have had to resort to working on more than one project in order to make a somewhat viable income.