My boss last week ask it to me, he thinking that know how dev, but know just a theory. In your vision, developing back-end is better because when you build a car, you first draw a motor and later you build a design of car and no after. That's because i have a experience from front-end on my career and never before developed the back, because of this i developing first on front and later i build a back.

And in your position?
What do you prefer? Dev back or front first?