Sector-level bounce vs sector-level reversal — what actually separates them?

Been trying to get more rigorous about this at the sector level rather than the single-name level. When a whole group sells off hard and then turns up, the individual chartsall look the same either way — reclaim, higher low, volume comes back. But a sector can do all of that and still just be an oversold bounce inside a broader downtrend.

What I'm trying to figure out is whether there are signals that only exist at the group level, not on any one chart. Things I've been watching, no idea which of these actually carry information:

— breadth: how many names in the group are participating vs just the two or three megacaps carrying the index

— leadership rotation: does the same name lead the bounce that led the decline, or does leadership change hands

— relative strength vs the broad market: is the group outperforming on down days, or only on up days

— whether the laggards start catching up, or the gap keeps widening

AI/semis is the obvious live example right now, but I'm more interested in the general question than a call on the group.

For those of you who trade sectors rather than single names — what's your top signal that a group has actually turned rather than just bounced?