When I was younger I used to snap up domain names for every little idea I had. I executed on less than 1% of those ideas and ended up letting the domain expire 1-2 years later when I could finally admit to myself I was never going to pursue it. Literally hundreds of dollars flushed down the toilet all to get a temporary rush.
I know that I have issues with thinking "spending money" === "making progress" (be it on home improvement projects or web apps) and I know I'm not alone. If all you need is a domain to launch your product then go ahead and start looking, otherwise it's just a dopamine distraction.