It wasn't for no reason, it was to get another artist so he could focus on other things, but clearly, it did not go as easily as planned.
It never does. I can't think of any games on this site where the developer starting to make enough money to hire additional people actually resulted in the game being finished more quickly.
In the best case scenarios they managed to keep the same pace of content output, but with slightly increased quality. Like adding more/better animations when before they weren't able to.
In most cases the pace of content output actually decreases, sometimes significantly.
I assume this is because most people who are good at doing one person development are not necessarily good at managing other people (including the HR/accounting aspect of it) and at managing projects. All the frictions that arise from suddenly having to coordinate and communicate tasks between multiple people, including the fact that a one person developer probably didn't exactly document all the stuff they had been doing particularly well.
And, there is probably the idea among at least some of those developers that now that they busted their asses to become successful, they can take the foot off the gas and not quite bust their asses so much by hiring other people to do that work instead.
So instead of one fairly talented and motivated developer (I assume if they make a game that is successful they have some relevant talents) being able to focus most of their efforts on creating the game, now that fairly talented and motivated developer spends much of their time and effort trying to wrangle work out of people who are most likely not as talented and motivated. And that developer is likely not particularly talented at that kind of project management.
Now I wouldn't want to dictate to developers what they do or how they try to manage their businesses as I am a non-paying pirate consumer. But I have started to immediately assume the game is about to enter a very troubled period of development with much slower updates when I see developers excitedly make updates about how they are going to hire people to help them. But if they have dreams of leading a team of developers, I guess that is part of chasing that dream.
I would much rather they just keep banking all that money and keep on working like they had been. Maybe they could try to contract out certain tasks that they can clearly define, but even that might wind up being a huge distraction and time/money sink if they aren't able to get what they need out of the contractor. Either because the contractor is not that competent or because they didn't properly define the work they needed that contractor to do.
If they want to have a team of people, I think starting that on their next project is a much better approach. They can plan it that way from that start and not try to bring several new people onto a project midstream. And they may want to consider actually hiring some kind of project manager, or at least taking some project management courses themselves, if they do plan on having a team.