...what keeps you from being happy.
When you tie your happiness to anything outside of your very being, your joy is at the mercy of that person, place, or thing.
Whether that's a possession, an achievement, status, influence, significance, authority, or whatever, realize you're bound by that very thing.
Start flirting with the notion of unconditional happiness by mentally taking away the things you've conditioned yourself to associate with it, and there you'll discover the drivers behind your attachments.
Once identified, consider its symbolism, and in many cases, you'll discover a deep-seated need for control.
The solution to encountering unlimited joy is surrender, and there you'll find you can be happy with less and less--that's freedom!
"The root of suffering is attachment." Buddha