What does this quote mean to you? "you cant have a better tomorrow if youre still thinking about yesterday"

It means you can't enjoy the future if your stuck remembering the past. great life lesson too

The past is lovely to reflect on every now and then but to not let it be a hindrance to my future. Our future, our better tomorrow, can only prosper when I am aware of myself and aware of my consequences to lead to a better tomorrow. It could also be that what ever happened the previous day shall not vanish if constantly thought about, one must put effort to make change. This is what it means to me. 

He is a humble person