Why is speed important, beyond attacking first (and all subsequent effects following attacking first)?

Since I started playing Pokemon 20 years ago I have always figured that Speed is the most redundant stat, in that aside from attacking first, which in essence offsets battle by half a turn (one turn counting each Pokemon attacking in a single battle), it really has no role. However, many guides, user comments, tutorials, etc. have suggested that speed is a very crucial, if not the most crucial stat in the game. Why is this?

I understand the basic necessities of speed. A half turn could determine the fate of your battle, most definitely. There are also other effects that are given to moves that attack first, such as flinching effects, or moves that are stronger when the user’s speed is faster. I get that. But aside from having a decent speed, I see users try to maximize their speed, on Pokemon that do not possess these kinds of moves. That is, 252 EVs, 31 IVs, and a speed boosting nature. And again, it all just seems so vestigial to me. What is so important about having a Pokemon that fast that you would be willing to give up EVs and nature for offensive or defensive stats?

I know this post seems ambiguous but I am genuinely confused. I don’t consider myself an amateur Pokemon player; it’s just this one trait that has always boggled my mind.

Pleaselog inorregisterto add a comment.

Saying that speed isn’t important is kinda outrageous.

Speed is vital especially in competitive battling. If your playing ingame then it might not be as important, but speed is still important. When your battling you would sometimes worry, “what moves does the other opponent have, will it ko me?” or “I need to use this move first. If not, I’m screwed”. Sure you might not think this playing ingame but competitive battlers would take this very seriously. And besides, most Pokemon have defenses and hp so low, it is not worth investing evs on them, so people try to ko the other Pokemon before they get ko’d.

This is also why people use priority moves like aqua jet to finish of Pokemon which are weakened and have low hp left.

I might as well add this:

I feel like another big reason for this are the speed ties as well. Pokemon like Latios, if they’re faster, knock out opposing Latios or win a speed tie. If your opponent runs more speed than you, then you just lost your Latios over something that could have possibly been prevented.commented 4 hours ago by Unknown Letter Q

This is my personal opinion as a Pokemon showdown player.