Sales and fitness are so similar, which is why I love both.
Consistency trumps all and both require a sense of delayed gratification. 

One quarter you can be blasting your quota by 200% 
the next your motivation is next to zero and you’re at 33% to quota. 

One quarter won’t kill your year if you just ride it out. Just like a few bad workouts won’t kill your physique. 

If you look at both from a long-term view, you won’t lose. Easier said than done most days.