Holding coins long term is also risky especially if you don't know for sure what tokens you are holding, so actually holding coins short or long term doesn't matter as long as you know about the project and have done your research beforehand.
Many investors had made this same mistake thinking holding a coin means keeping the coin forever. Holding should be more of timing than leaving a coin for longer periods without trying to sell and buy it again or other alternative coins.
Some token Ard only meant to stay for short periods of time below losing it value. This is why more of these shit coins we are keeping now might be forgone in few years from now.