Honestly, if your content is good, all the more you should put some effort on your thumbnails. Don't feel bad about it. To me it's like spending your lifetime

Honestly, if your content is good, all the more you should put some effort on your thumbnails. Don't feel bad about it. To me it's like spending your lifetime writing an amazing book, only to spend a few minutes on designing the cover. It could be an amazing video/book. But how would I as the customer know? I (and probably many other people) are constantly searching for good videos to watch. And unlike books, it's so easy to take a peek on a video and decide to close it within seconds if it's not something that is interesting to me.