I find dips good even if I have invested a lot already. Even though my portfolio value decreases I still invest and buy more since I know coin price will boom ultimately. I only invest in good coins only. Also, I only buy when there is a flash crash or something like that. Usually, have bids placed at lower values to catch the coin in dip. Never been wrong till now.
But many times the dips are big and it takes time for good coins value to rise. Many investors get scared because of this.