The only limit to your impact is your imagination and commitment.
I think this is a pretty great sentiment. If you thought that I came up with it, it might not mean too much because I'm just some guy.
"The only limit to your impact is your imagination and commitment." - Tony Robbins
Now this statement is a quote. And, it's a quote by nationally renowned motivational speaker Tony Robbins. As a quote, it has increased value, which is directly attached to the value of its speaker.
"The only limit to your impact is your imagination and commitment." - Joseph Stalin
Now this statement is a quote by one of history's greatest monsters. Is the sentiment in the quote any less valid? Empirically, no, it isn't. But quotes are valued based on their speaker, so now it is a sentiment that should not be shared; it should, in fact, be abhorred.
This is one of those silly, ridiculous things about people. We truly are irrational creatures, but at least we are somewhat consistent in our rationality. When you bring up quotes, the speaker matters more than the words. The same generic sentiments have been said by thousands of other people, so the only reason to put quotation marks around it is to ride on the fame (or infamy) of one person that shared it.
What I would recommend to you, though, if you wish to be a deeper thinker, is to seek out famous quotes by famous people, but analyze their words instead of their speaker. There will be a natural bias in this endeavor (nobody likes to share positive quotes from Stalin), but you may uncover some interesting ideas that you would normally pay no mind to.