Won't that stop you from achieving certain goals you have in your life? I mean, if you say "I hope one day I will be the greatest xy" then you will do everything do achieve this. If you say "I don't care how this ends up" and you don't care you won't achieve anything because there are other people who DO care and who are working to achieve a "certain end". And they probably will. Or at least more likely than you.
Hope without action is useless and meaningless. It's best left for situations where you truly have no agency and recognise that there is nothing you can do to affect an outcome or where you wish to acknowledge that you don't intend taking action.
Desire can be both a source of motivation and a source of frustration and misery - thus the Buddhist belief that attachment to desire is the source of all suffering.
Action is what tends to create results. You're more likely to achieve desired outcomes while thinking negatively but taking action than you are by thinking positively but doing nothing.