Built my Gaming PC 2yrs ago, need to know if this is a safeguard or something else.

TL;DR at bottom

When i first built my PC, the first time i clicked the power button, it turned on for a few seconds and then turned back off, i panicked but on a 2nd boot everything went fine, two months go buy and one day i go to turn on my computer and it did it again but resolved on the 2nd boot. It happened a total of twice in the first year and maybe two or three more times on year two.

I thought it's possible i have/had a faulty psu but i never had my PC shut off from hard gaming and still haven't today. I took a closer look at my power button cords a few months ago and it looks like it could be most likely from my power button cord being loose and sometimes pressing it does not send a enough power to the motherboard i presume.

I tried to to push it in but it was not plugged into a slot at all but looked like the end was soldered onto a board instead, i guess that was just how the case was designed, either way never buying a Phanteks case again.

Anyways, in regards to the original title of the post, i want to know if this was a safeguard to prevent damage done to my PC, i had a bad power outage earlier that had the power go on and off 3 times before turning back on within a few seconds. I safely decided to keep my PC off for the time being incase the power went back off and now here we are, i went to turn on my PC and nothing, 1 second later i push the button again and it boots. Btw my PC is plugged into a power strip surge protector if that helps. This was the first time this has happened btw, ive had a couple of power surges that has gotten me before when my PC was on and this is a first.

TL;DR: PC did not boot until clicking button again after bad power outage.