At Diamond and S-Tier, a single mistake often destroys your chances of winning. So too does a +1.5σ difference in draw quality between your opponent and yourself.
Usually it’s evident by turn 3 if a match is completely one-sided due to rng or error, and then the prudent move would be to resign so that nobody wastes time. However, this causes the match to not count towards quests or xp, which is a significant disincentive. The penalty should be lifted for skilled players at this point, given that the outcome of a match is effectively determined, yet still takes several turns to actually end.
Roughly, I would estimate this occurs 1 out of every 8 matches, just often enough that I’m sufficiently annoyed to offer this suggestion.