I noticed that when you start on a project with a beginner mind (for that particular product) you have a fresh approach and start noticing a lot of bugs.
After a while and some experience with that product you stop noticing many new bugs and start being habituated with the product and eventually noticing less and less faults. And I think this "effect" could affect everything from API testing, automation to making an all-encompassing test plan.
What would be the best approach to stop this psychological mechanism and obtain a "fresh mind" approach on the product?