I am introspective. Which is good in the sense that I try my best to be honest about my own strengths and weaknesses, about mistakes I've made, and things I can do differently in the future.
Speaking for myself though, too much introspection is dangerous in its own way, because it'll sometimes lead to ruminating. I think I spend too much time in my own thoughts at times, and I'll sometimes beat myself up over things that have already happened and nothing can be done about them. It's a fine line between healthy self-reflection, channeled into action when necessary, and just lingering on things that can't be changed.
But I'm working on it and getting better at staying introspective without ruminating