If your investing then you are going to be long in the market and holding a stock 3 to 5 yrs. It's all about Managing Risk! How much are you willing to lose and how long are you willing to wait for a good return. Holding on to a good stock will be beneficial, but you have to stomach the dips as the stock still climbs. Also, some stocks pay dividends too.

If you are a long investor can buy a stock over and over, load up on something like Nvidia, Apple, Tesla, anything that has over a billion in Market Cap, a solid trend upward (even with dips) that is also doing well. You will need to look at a 1 yr chart. Check out https://www.fool.com/ or https://finance.yahoo.com/