Geoffrey James, author of Business Without the Bullsh*t: 49 Secrets and Shortcuts You Need to Know, sums this one up perfectly on Inc.com;
“I will try…”
There are no three words in the English language that are more deceptive, both to the person who says them and the person who hears them.
People who say “I will try” have given themselves permission to fail. No matter what happens, they can always claim that they “tried.”
James adds, “People who really and truly achieve goals never say ‘I will try.'” Instead of saying this phrase, “they always say ‘I will do’ something or, better yet, ‘I must do’ whatever the task is.”