Thinking has no endpoint, and people who are smart can think in circles

You don't know what works (and what the actual bugs, issues, and important details are) until you put your hands in the clay, so to speak

Let the clay (your project) have some say in what it becomes, or else you come to every problem with a solution you crafted in your head and have no time or space left to come up with a better-fitting solution

A problem that stops you and requires a day of thinking is one that needs to be approached differently so you can make progress every day. We don't know how many days we have left, don't think all day today and do nothing, leaving that for tomorrow.