I like David's answer..."Shoulds" are part of the reason many of us became Entrepreneurs.
The definition of success is completely based on your goal and objectives.
Before deciding how to measure success, you must define what it is for you and your company. Is it purely a monetary number? Is it related to company culture or charitable impact?

I have clients for whom "success" is not about money at all. Thus their measurement system is completely different than one connected to numbers.
My question back to you is: What is your primary goal for your company? How will you know when you've reached that goal?