When I was a young lawyer, a more senior attorney told me how important it was to participate in a full blown trial. Only there, he said, could I learn the importance of all the preparation we did before trial.
Basketball is similar. All players work on their games for years, and all teams spend more time on the practice court than they do in games. But all that individual and team work is mere preparation for the relatively short time spent in games.
A good argument can be made that all the regular season games are just more preparation for the playoffs.