Doing something is better than doing nothing.
This is an existential statement. You can always choose action or non-action. "Action" and "non-action" are terms that refer to the quality of being. You are either engaged in some kind of activity or you have chosen not to do any activity. For example, you have chosen to think. Thinking and doing are different qualities of being.
If you have chosen to do some action but don't produce any value or make no useful effort, then better start doing something valuable. Then the quoted statement makes sense.
On the other hand, it is perfectly ok to do nothing or to choose non-action. Then you are excluded from any positive or negation reactions to your doing or your actions. You stand in the neutral position and nature or existence doesn't gives you back any reaction. According to my understanding, this is neutrality.