When it is falling, a lot of people will ask you to buy or to hold, but you should look for the reasons why the price is falling, if its caused by usual correction then holding or buying is already correct, but if you found something suspicious, like the coin developer want to scammed people or there are weakness in the coin, then you should sell, investing in alt coin need patience and need a strong mind
You are quite correct. Investing in altcoins needs calmness and patience. But the main point is knowing which altcoins to invest in. Some of us newbies are really confused when it comes to that.