Mindset is very important, because your mindset is what will drive, if you dismiss something in your mind, then no matter how hard you try to make it work it won't because your mind has already dismiss it, mindset plays an important role in whatever we do, that's why it's always advisable to have the right mindset towards work, it's a mental conditioning that helps with success.
In my opinion the best way to have the right mindset is to stick to one thing if you really want to make money online, jumping around on any shiny things will not help you, in terms of productivity and long term results.