When markets are up, everyone thinks all is well, markets are bound to rise higher perpetually. It is at this moment, there’s most risk involved in fresh buying.
When markets are low and every Tom, Dick & Harry knows that it is going to go down even more, there’s least risk involved in fresh buying.
The greatest trick market plays at extremes is that it rewards & punishes you when you least expect it to be.
To a certain extent, from my personal experience, same principles applies to life too.