Choose the activity before the letter
S, A and B describe QuestBase's current editorial fit under the stated activity assumptions, not a universal strength score or measured clear-time record. A class can land differently in each activity because targeting, resource recovery and movement requirements differ.
Read each entry's reason, then open the linked build for progression, gear and failure cases. Blizzard's official patch record remains the source for changed mechanics; a third-party tier list is only a cross-check.
How the bands are assigned
S means the build's normal loop addresses the activity directly and has a comparatively understandable route to repeatable clears. A means it can be effective but asks for more specific positioning, gear or execution. B remains playable; a known limitation makes it less convenient for the named task.
These are fit bands, so they do not claim that every S route deals more damage than every A route. A specialized boss build may fall behind a broad farming build when ordinary packs and travel time dominate. Conversely, a farming route can lose its edge when a boss removes its on-kill resource engine.
The linked build page explains that limitation and offers a progression path. Use the letter as a short navigation aid, then make the actual choice from your character's available gear, expansion access and preferred combat rhythm.
What can change during Season 15
A dated patch can alter a skill tag, item trigger, resource interaction or activity reward. Revisit the affected build after such a change rather than carrying its former band forward by habit. The four lists state their Season 15 context and last update, but Blizzard's maintained patch record remains authoritative for exact live rules.
QuestBase has not run a standardized clear-time benchmark across all eight classes. The bands are original editorial comparisons of documented loops and likely activity fit. If your own repeated runs differ, the first question is whether the assumed gear, route and encounter match your character.
Sources and verification
Official Blizzard material establishes named mechanics and access. QuestBase labels progression and build advice as editorial judgment. Exact live values should be checked in the client and maintained patch record.