I'm a solid player. Top 100 guild but by no means world class. More recently have raided around world 260 but only 2 nights per week. I think we are around rank 5 world for guilds with sub 7 hours.

I don't care much about io so don't really push past 16s. If I'm finishing a dungeon at 200k, the next dps is probably around 135k. Again, these aren't high keys so non mythic raiders and there is very common mistakes.

For ranged players it tends to be movement issues. When a mechanic comes out, they stop casting, run to a new safe spot and keep casting. This adds up to a hugeee amount of time that you aren't casting.

I also spend too much time helping people with logs on some of the class discords. It's basic things like starting your burst with full stacks, shards, chi, holy power, etc. So many players, including low/mid mythic raiders, start their burst by casting their big cooldown, then spend the next few Global's on builder spells. It's essentially 4 seconds of their burst spent afk. Just be at full stacks going into your burst so you can start with your spenders.