To be more on-topic, Evasion is quite simply the icing on the inconsistent cake. It only needs a single boost in the correct defense, or in speed, to become very threatening and start a full out many turn setup, depending upon what is out against it.
FUCKING THANK YOU.
This is what I truly feel about inconsistent - it's not based on evasion (which you guys seem to be WAY overexaggerating) but on getting boosts in the right stat at the right time. A speed boost is, by far, the most important boost to get for my glalie. If I get one that means I outspeed everything in the metagame but like... scarfed base 120s or something like that. at that point it's just a matter of getting a sub up or stalling the maximum 8 turns until I accrue enough boosts.
My point is:
Inconsistent (on Glalie, at least) is not broken due to evasion boosts. Hell evasion will only affect you... like what 2/21 of the time on a turn? those are, frankly, terrible odds. Inconsistent is OP mostly due to the speed boosts - if you get one, you can stall the time and the boosts you need will simply come over the 8 turns... at that point only priority and breloom bullet seed (implies you are slower by that point) can screw you over. Hell if you even get one sub up you really will win.