After watching threads come and go it is evident that a lot of threads similar to this are for the purpose of getting attention.
It is getting dramatic though lol.
Whether it's three sets and a warm-up before you increase weight... This is just one variable of many that you have to experiment with until you learn. Trying to learn ON CYCLE is adding a very complex variable that will mess up the results making you draw faulty conclusions. In essence what you are doing may be very bad methods at way below maximum intensity, but on cycle on a body that has not yet been accustomed to weight training it will give results anyway.
You need to, over along period of time, figure out how much work you can do without getting to the point of diminishing returns, per workout. That is, how many exercises, muscles etc per workout. Then figure out frequency, is it worth it doing less work per session and train more frequently or not? Or is it even worth it doing more work and resting longer? How many weeks before you need to change exercises, rep range, utilizing other techniques like dropsets, negatives et.c. There are even set out programs where you can try a different approach, log the results over say a 4-6 month period, compare with other programs you have tried and see if 4-6 months yielded better results... Once you've done this you'll understand where everyone is coming from.
Start a journal in the workout section, you're going to get much better responses than starting a log of a test E cycle when you're incline benching 42,5kg and getting injured lol.
You will also get time to contemplate on whether lifting is your passion and if the side effects are something you accept vs the gains.