A productive person is not necessarily a hard working or disciplined person. They are the person who finishes things. Read on ...
@wesbos did an ama last year and this was my favourite answer
Q. How are you so productive Wes?
A. I always loose steam on things right about 90% o the way through. That last 10% is the hardest. Learning how to push through and finish everything I start has helped a lot.
I have 5 projects right now which are 90% done. Instead of loading my plate with more from the buffet I've got to just finish things.
I would estimate that 80% of projects go unfinished. Why?
a) People bite off too much
b) People get started in a fit of excitement, which fizzles out
So Before you start another project ask yourself, "Am I truly, honestly, 100%, going to finish this project?". Be deadly honest. Give yourself 24 hours to think, so the initial excitement wears off. And if you can't decide the answer is no.