An Aave position lost nearly half its collateral on September 15.
It didn't happen in one move. It took eight small borrows over three weeks.
From late August the owner kept borrowing against wstETH: $300, $250, $100, $100, $250, $150, $20, $50.
After each one the cushion got thinner. Its health factor dipped under 1.05 a dozen times along the way.
The last $50 took it from 1.064 to 1.040. 19 hours later wstETH was down ~4%, and a liquidator took ~$1,270 of collateral.
Without that last $50 it would have survived the block, but only for about 5 hours.
No single borrow killed this position. Together they left it nothing to absorb a normal 4% move.
Glider Monitor tracks the health factor every block, so the slide is visible from the first time it crosses your line, weeks before the liquidation.