In technical sports like throwing and weightlifting, the most important aspect is fairly obvious: technique. You can only get so good in either of these sports if you approach them trying to achieve anything less than technical mastery. Unfortunately, and because nothing worth having is ever easy, the road to technical proficiency is a very long one. While the challenges are both physical and mental, I think the mental aspect of technical sports is the one that requires the most attention. First, you have to have a very clear understanding of what you want your body to do. Find your technical models and stick to them. This is one place where a coach with an established system is invaluable. Having a well-trained, knowledgeable set of eyes on you for all or most of your reps is key in helping you consistently attack that technical model.
Second, you have to have the mental fortitude to attack those technical adaptations, every session and every day for (probably) years. And as soon as you’ve nailed one flaw, there will be another one to work on. Sometimes, when you move to the next key technical point, the last one you fixed starts to fall by the wayside again. Technical adaptation is the ultimate example of the true shape of the path of success: a winding, curvy trail that sometimes doesn’t seem to have a clear end to it. You have to trust that the changes you’re making will work for you in the long run, especially when they don’t seem to be working right away (which is usually the case). It’s not going to be easy, or particularly fun sometimes, so you really do need to have a clear idea of just how good you want to be. This will really inform how much focus and effort you need to have. If you want to be the best, you have to dedicate yourself completely to each technical change.