This is why having multiple projects at once is actually an advantage, and can help you finish projects. When you come across a blocker, having a second project can be a relief. The trick is to have games that require separate skillsets, goals, and overall and types of thinking. This way, switching from one to the other allows you to recharge.
For game development specifically, the action-fumblecore game KickChick has multiplayer and requires lots of programming, while the document manager game Grandma Simulator requires a focus on designing UI and narrative. When I hit a blocker on the programming for KickChick, I worked for a few hours (still no programming mentor yet!) and the lines of code seemed like they were blending into each other. Grandma Simulator allowed me to relax and focus on UI.
This is the same logic that people apply to recommending that people have hobbies, but since I enjoy game development — and want to finish my games — this is a great alternative. At a workplace, such as some of my previous internships, I requested additional work because I had the capacity for it, but having extra projects could also help you build a better workflow.