Unlearning a bad habit is harder than learning a good one. That’s why it’s worth doing early.

A habit builds a path, and building a new path is easier than closing an old one, because the old one stays available long after you stop using it. That is why early is cheaper. Ten weeks of something is a light edit and ten years of it is a renovation, and a technique picked up wrong at the start is the one that has to be taken apart later.

Look at whatever you are learning right now and check the form early. Ask someone who knows whether you are doing it correctly, before the reps pile up behind you.