This might be a stupid question but when do you decide to finesse fish compared to power fish? Is it weather? How many bites you are getting? Only technique specific?

Not a stupid question. For me, if they are not taking the more aggressive moving baits or "power fishing" techniques, then it makes sense to change it up. Also, winter and colder water temps can get those fish more attracted to a more subtle presentation. Some may disagree, but that is my answer for where I am in my fishing learning.

I feel like "finesse" fishing will usually generate more bites, esp in winter.
That doesn't automatically translate into a successful day if your tournament fishing - there are plenty of days that I will throw a bait knowing I am only going to get 8-10 bites on a particular bait and I'm ok with that. I just need the right 5 and catching a bunch of 1.5-2lb fish just isn't going to help me.

Fish for winning fish was the best tournament advice I ever read/heard.

If your on a lake that is going to take 20 pounds to win, then you need to be fishing for 4 pound fish. Finesse might get you that average but likely not.

Nonetheless, sometimes you just need a bite to get into the right frame of mind.

For example I have a spinning setup with 10 pound line that I wacky and Neko rig and I get big bites and small bites with this setup.

I think there is a time and a place for both and what you are trying to accomplish. As was said above, if you are in a tournament and having to put up 20+ pounds to get in the money, power fishing for sure. Fishing from the back of the boat in a tournament as an amateur, I'm putting weighable fish in the boat so finesse fishing for that situation. Just out on the water for an enjoyable day of fishing? I'll start out throwing normal size lures but if they aren't to interest, I'll switch over to finesse fishing.