One of the best things you can do for the progression of yourself and the people around you is learning to say the word "No."
This is something that I personally struggled with for a long time...
...and because of it, I often found myself frustrated and bitter.
Understand that you're not hurting people or letting anyone down by saying no…
Oftentimes, people need to hear the word “No” in order to have the difficult conversation with themselves to improve.
Quit undermining your confidence, productivity, and sanity.
Learn to say the word "No" … and get used to saying it clearly and often...
Everything in your life will improve as a result.