Know Your Self-Worth
You can only accomplish what your self-worth allows you to achieve.
If you don't think you're worth much, you won't accomplish much.
Now, there's a difference between being humble and being arrogant. The difference is, there is a lot of self-evaluation, self-awareness, and realizing, "I'm worth a lot. I can achieve a lot."
Being 'worth a lot' is understanding you're a person of value that has value to add to other people. And that's the big difference between thinking a lot of yourself and not thinking of others.
When you think about others and think enough about yourself to appreciate who you are and what value you have, then you can make a real difference.
Through that, what you know about yourself appreciate, and you believe you are a 10 out of 10, you can serve people 10 out of 10.
If you only believe you're a two or three out of 10, then you're only going to be able to serve people at a two or three out of 10.
Know your self-worth.
That's what's going to allow you to achieve.