>>54813976A big part of team building is to simply understand what it is that stops your prefered wincon from winning and also what harms your team the most. These are things that you can only grasp if you experience them repeatedly, they arent really a theory/research based process.
>building around a winconFor example if you have a pokemon like greninja, its important to see what comes in to sponge the hits from greninja and put something on your team that can either lure those pokemon or something that you can easily double switch to and punish the opponent. As long as you have the greninja they have to keep their checks alive and healthy which means greninja acts as a sort of bait to line up other offensive pokemon, alternatively you could run a lure set and kill/cripple the pokemon but you need to know more meta relevant things to do this. For example azumaril used to be run as a partner for greninja because they both shared the same counters in past gens but azumaril could run a perish trapping set to kill all of greninjas counters. Sometimes its worth running multiple pokemon that share the same counter just so that you can wear them down with one pokemon and clean up with the other one. Other times its worth running pokemon that take advantage of bringing in a certain counter so that you have an opportunity to bring in the counter to their pokemon and preserve your momentum.