Nothing can run at 110%, 100% of the time; but so many sales people try. It reminds me of an old poem by Edna St. Vincent Millay.
“My candle burns at both ends
It will not last the night;
But ah, my foes, and oh, my friends –
It gives a lovely light.”
Burnout is real, and it’s coming for you. Working nights and weekends may get you off your PIP, but you can’t build a career that way. You just won’t make it. Building a good balance between work and rest is easier the earlier in your career you do it, but it’s never too late.