Nearly every interaction we have with others, we have some goal. We are selling ourselves, our message, our goal. Whether it's a job interview or getting a date...it's sales. You're selling yourself, your idea, your product, etc. to others.
For work, I've had to do public speaking / product demos at large events / technical conferences to dozens, hundreds and thousands of people, including unscripted Q&A sessions after my presentations. I've been doing this for decades, and I have a team of younger sales people that I help with their presentations to make them more effective, focused, organized and targeted for the objectives (ours and our clients').
Before my presentations, and now before people on my team present to our clients, we do dry runs / practice; and I critique - what works, what doesn't, and things they do that are distracting, show weakness or uncertainty etc.
j/k
