What's stopping me from just infinitely looping moves that are plus on block? Wouldn't this make it physically impossible for your opponent to do anything?

Complete beginner confused about plus frames.

If a move is plus on block... then... can't you just infinitely attack since you'll always have the advantage?

For example, almost all characters have a 10 frame jab which is their fastest move possible. My main's 10 frame jab is +1 on block.

Can I not just spam jab over and over? If they block, I have +1 advantage. Even if they immediately try to attack me with their fastest move, my jab will beat their jab because I'm +1. If they block, I'm +1 again. And if I do manage to hit them, I'm +8 which gives me even more advantage. Since my jab is my fastest move, wouldn't spamming jab just beat everything as long as they don't try anything else like ducking or throwing etc.?

Similarly, what's stopping me from ONLY using moves that are plus on block? For example I could do move A (+4 on block) and follow it up with a 12f move (+6 on block, still beats their jab because 12f effectively becomes 8f which beats their jab), then a 14f move which is also plus on block, etc. etc.? Wouldn't this just allow me to attack over and over without ever giving up my turn whether they block or not?

I already know that this doesn't work, but idk WHY (like the conceptual reason behind why it doesn't work). Why can they suddenly block or counterhit or get their attack out faster despite my +1 advantage? How does this work?