Unfortunately, this is in large part due to a lack of passion for such upon yeur part.
The real question people should be asking themselves, is "can I do better than this?". So long as the answer to that question is "yes", it's not done.
It's true that the purpose behind an ability is important, and that numbers are only there to represent concepts, but a number is a far more fine sand for balancing the scales with. "High damage" is nice to say and all, but how high is high?
Does "high damage" mean high DPS output? Does it mean high burst but low DPS? Does it mean high in relation to other champions, or high in relation to the designer's own personal views on whot high and low are? Is 300 damage high, or is 350 high?
To put it bluntly, the difference of as little as a 0.1 AP scaling coefficient can make a big difference, and "high damage" doesn't really clarify that point very well.
Regardless, the fact of the matter is that, if yeu're going to half-ass it, why even bother in the first place? If yeu want to make something, make it as perfect as possible.
If yeu want the truth, what people who actually design games professionally are going to think, is that there might be one or two slight hints of a vaguely neat idea, but overall, they're unimpressed by someone who doesn't show any real passion in their work.
QUICK, NEW CHAMPION! BOB THE NECROMANCER!
Passive: Collects bones as minions die around him.
Q: Fires a spear of bone fragments in a straight line.
W: Summons a melee skeleton from bones to fight for a short time.
E: Detonates a skeleton to deal AoE damage.
R: Summons a powerful golem to fight for you.
Oh... yeah, I kind of just described the Diablo 2 necromancer. Right. It's also remarkably undetailed, and without knowing the source material, it doesn't tell the reader much of anything. Does the bone spear stop when it hits a minion or champion? Does it consume bone fragments? Since summoned units are very powerful due to their "throw away" nature, how powerful is that supposedly powerful golem, anyway?
More information only shows yeu've thought about it more and have put more effort into it. Yeu may make mistakes, and they may be big ones, but at least yeu're trying.
Personally, I'd rather see someone show they have the drive to at least try to balance their champion. They don't necessarily have to succeed, so much as show they know roughly where they want the various stats and abilities to be.
Or yeu could just get bored and give up in 10 minutes and suck, then request everyone else do the same so that yeu don't look as bad.
People don't post here because they want to spam out an idea in 10 minutes and leave it that way; they do so for a variety of reasons. Some of these relate to being used in the game, others just enjoy making them. Regardless of the reasoning, however, more information and passion in yeur design is virtually always preferable to less.