What is up with protoss players running their entire army through entrenched positions?

Like genuinely, I don't get it. You look at the top pro terrans and zergs and they have not only great skill but actual methodology and understanding of the game.

You look at how flash plays and most of his moves have logic to them, same with soulkey imo.

But then you look at some of the top toss players in the world, and they consistently do the most insane shit in PvT. And the number one offender is this need to attack when there's no reason to.

I think every other top player in other races understands this concept. But I see so many games decided just because the Protoss player throws his entire army into a line of siege tanks and vulture mines instead of just expanding and teching up. I don't know it's just ridiculous at this point, just sit back, get an insane number of bases, get all the tech you need, get all the production you need, get all the money you need and force the terran to attack you when you're in a much better position.

Which then opens up possible counter attacks and so on. Also what's up with only picking up one tech line in late game scenarios. Shuttle templar and arbiter aren't mutually exclusive, you can go both, you're banking up 3k gas you can afford that shit easily.

Anyway sorry for the rant but yeah, I really don't get it. It's like charge of the light brigade 24/7, I swear if protoss players stopped doing that their PvT winrate would shoot up by 5% easily. So many games thrown away.