For the past week I've been warning BTC's correction still had another leg down. Two very powerful indicators predicted BTC's continued correction to the 8-10k area.
1 - The 150EMA which BTC has respected religiously.
2 - The Elliott Wave Zig Zag count
The goal of markets is to trick you. When buyers are at their happiest, markets correct until buyers feel pain. When the correction runs so deep that buyers are screaming with pain, liquidating underwater positions, and fed up with the correction; that's when markets revert.
That's also why markets revert, since all bulls have capitulated to bears, leaving no more selling pressure to fall.
Technical analysis charts this emotion. Make no mistake crypto is some of the most emotional and irrational markets of all. A majority of the participants have never traded, and don't understand why they're on the wrong side of the market.
So a real world indicator to look for (in addition to TA) is permabulls screaming in pain and running for the hills. I've seen a few already but unfortunately there will need to be more before this market has a POTENTIAL of resuming. There's still the outside chance this is the end of the bubble.
Hope this helps. It's not trading advice. Always trade based on your own analysis and assume your own risk. Never risk more than you can afford to lose entirely.