I have wondered where the conversation around IGLs ends for a while, so here I go starting it. If one was to realistically create criteria for quantifying and accurately measuring which IGLs are good, unlike other roles where you can take KAST, ADR, Clutches, etc. into account and create parity, it becomes difficult for an IGL as you cannot evaluate strategy, mid-rounding and just leadership objectively. Like how do you rate leadership? A good leader can lead in different ways, command respect in different avenues, etc.
Now, I am a football fan and one way a "captain" is evaluated, like Xavi in Barcelona, Gundogan in Man City (in terms of a good leader) or Harry Maguire in Man United (lol) for a study around what quality leaders provide and the only legit criteria I found was "improvement". Why is this the case? Imagine you have two equal-quality teams, in this situation, the better IGL would navigate a win 10/10 times if they played. Now if it's like a team with players 20% better, in that case, the same repeated would yield 8 wins if they played 10 times. Now, therefore, an evaluation of how much better a team or a group of players look with the presence of a good IGL is the test for what a good IGL looks like, for example, look at the top tier 1 IGLs in the scene, people like Boaster, FNS, Sadhaak, etc. A comparison would look like Marved at Sentinels, like clearly a terrible IGL because the team looked way worse qualitatively than with a different leader or IGL.
With this context, what's the community's opinion on IGLs? Gimme a top 10 including tier 2 and tier 3, I honestly think Hellranger is up there.