One answer to the headline question might be, "because a lot of people think that you can't "teach" sales success, that successful sales people are "born" not "made."  There is some truth in this. However...many enormously successful sales people (during my career, I knew quite a few) had no training, (some studiously avoided training), most were self-taught, some were semi-literate and uncouth, a few were physically ugly, and the most literate of some I knew were only middling successes, despite their degrees.  

My success was proof that you CAN learn enough to succeed pretty well in some sales situations (they aren't all the same: skills used at time-share breakfasts, in boardroom meetings and in noisy retail appliance department are all different...) 

"Let’s encourage our younger generations to embrace the sales professions."

Okay, but even better, teach them how to sell THEMSELVES.  Their futures depend upon it.