Hey there!
It's not a bad idea, especially around earnings time. Growth stocks can be fairly volatile and you may want to lock in some profits. You'll see where I use it on a stock below.
However, keep in mind we can't use stop losses here in Canada and have to use stop limits.
Stop losses have the potential to cause some pretty extensive losses. The reason being once your stop price is hit, the order initiates a market order and sells your stock for the best possible price it can get. If a stock "gaps" down, you can end up selling for substantially lower than what you'd like.
That is why a stop limit is the best method. You set your stop price, and then a limit you would sell at.
A prime example is the stop limit I currently have on Shopify.
The stock currently trades at $686. I have set a stop price of $600 on the stock, and a limit price of $580.
So what this will do, is when Shopify falls below $600, it will initiate a limit order and sell the stock only if it can get over $580.
I believe in Shopify, but I still want to protect some of my profits. Another added benefit is if it does hit my stop limit and my stocks are sold, I can buy back in if the price continues to fall and collect more shares.
You'll most often see where these stop limits will save you money right when the market opens. If Shopify trades at $601 and reports earnings after the bell, there is a chance the stock could open the next day substantially lower. If it opens at $540, your stop loss will sell your stock at $540. Your stop limit will hold on to the stock because you can't satisfy your limit price.
I hope this helped!