Long range = grey world

[k-bones]

(...)and there are many good counters with tele, air tanks, stuns, not as effective in mid and endgame etc...

THATS MY POINT you need a counter to that! When there is a guy with short range you can just stay away from him. And "long range isn't so effective in late game" is NOT an argument - long range guys can take the map (yes, they can take cps too, especially when they clear all creeps first) and then slowly switch to short or mid range, plus they have more money then (with scores about 30-2)

Conclusion: At the beginning long range is really strong but becomes weaker during the game
So why not to play always long range at the start?

Because there are other weapons and you could delete them as well. The desired situation is to make all strats equally effective when used by pros.

Long rang has a lot of weakness. Even at beginning of the game.
Lower dps, lower delay. The middle and low range just have to kill more creep than you until the 10 first minutes. Sometimes by luck, the long range get one kill but it is nothing comparing to gold he loses from not killing creeps.

Not true. Long range can stay out of any range in early game, which keeps you at full hp and allows to creep more because all stuns aren't powerfulk enough yet. You can kill many creeps without approaching your creeping enemy and getting under fire. Furthermore, long range basically forces the enemy to attack, which can end up pretty bad.

In early game I don't think you can last more than 30 secs without your hp falling to 50% when you are in green's range... (which is constant in mid, 2 greens taking the flag and terrorising the map)

Another thing - please stop referring to noobs/pros. Imagine a game in which one pro takes long an the other one takes LT/fireball... who kills more early? who gets hull early? who has to counter and spend more cash on nets/breakers? you tell me.