Mastering a single hero is already hard as it is with so many skill and item builds, not to speak about the combinations with other heroes, learning ranges and what not, so why should anyone spend more time learning more than two or three and use them in rotation?
Well, except for the surprise of finding more heroes that fit to your play-stile and adding to your flexibility, there are reasons why every pro player has went trough all heroes at list a few times. Usually, when you play a hero for the first time you have difficulty in getting your head straight with all the spells and items. You feel it’s too much to do or you are doing stuff in the wrong order. On the other side, you are learning its capabilities. How fast he moves, how hard he hits, how far he reaches and how often he can use his spells.
This might not seem much, but in game you will find yourself amazed by how much that means. If you have played Timbersaw a few times, you will learn how much he relies on his trees for the damage. The next time you will meet one in battle, you will know how to stay away from trees better than usual, because the first hand experience in trying it gave you an opportunity to see when you can miss. Or you will know that if he has just used a Timberchain, he will have at least three more seconds before doing that. This applies not only to spell dependent heroes, but to melee as well, because you will have a feel of how much someone can do with what he has.
By playing one of those OP heroes everybody talks about you might get a hard beating and learn what can counter him. If you always get beaten up by a Phantom Assassin, go ahead and pick it up the next game. You might see a naked Chaos Knight beating up your 4 slotted PA and understand what strengths and weaknesses it has.
On the other hand, by playing the same heroes over and over you will lose the opportunity to see someone else play them and thus learning new ways and item builds that could improve or help you develop new strategies.
Luckily the game supports you in this crazy quest of randomness both by different game option – All Random, Random Draft, Single Draft, as well as the Random button on normal games that will even benefit you with 200 gold bonus. Not to speak of the ALL HERO challenge.
So why pick another hero? Not only to get better at the game, but to get better at your favorite hero.
Massimiliano “Hit me!” Nugnes