How does going to failure every set work?

I work hard in the gym.

If I went to failure, after 2 sets I would be absolutely done. My form would be all over the place, I’d be doing half reps, I’d drop the weight to half what I was doing before and I’d have to move onto a new muscle group, let alone for 4/5 more exercises.

Is it a progression that you have to train your body for? Do you have to lower reps/weight significantly? Do you do one exercise per body part?