When I click on a YouTube video, I don’t see how many views or likes the video has, I click for the title. If the video I am watching doesn't captivate me in the first 5-6 seconds, I move on. Normally I do not give much attention to thumbnail, but thumbnail is also one of the reasons why people click on videos. You might bet people to click on your videos because you have used a great title and a thumbnail, but if your video does not captivate audience in first few seconds, your viewers will exit. Therefore, for building views and engagements, you need to produce good content.