Years ago, when I was training at a health club, I witnessed the success of one trainer and the demise of another. The first trainer was young, new to the industry, and eager. He made his share of mistakes but always learned from them. Most importantly, his attitude was top-notch. He was eternally happy, left his ego at the door and always let his clients know he was thrilled to see them.
The other trainer was an industry veteran. She was a solid technical trainer but had a sour attitude and bitter energy. She would arrive late to sessions and often commented on how she wished it were the weekend.
The young trainer grew his clientele quickly. His clients were more than willing to overlook his inexperience because they liked him so much. The veteran trainer saw her clientele dwindle. Eventually, she moved on to a different career because she could no longer make a living as a trainer.
In this business, you live and die by your attitude.