I trade Bitcoin, which is a major on my trading list, while touching other altcoins in fraction. Though, when the market is on a down trend, just as we are currently facing, I sell first to take out profits, then hold till a considerable buying position for myself. The deep is for new entry, just as some big crypto enthusiasts are filling up bags, with the deep as the major point, so do I in buying some altcoins and wait.
I often hold some promising coins for a long time, while others that I trade are mostly meme coins and Bitcoin or ETH.