What is the most important ingredient that increase motivation of a sales engineer?

to be able to

position your product, service, industry or market

to establish your clients' need

explain the benefits of your product in a tailored way

overcome objections

contains or access testimonials

Knowledge is the main ingredient that increase the motivation of sales engineer i.e.,one should be well known about their product/service what they are offering

A Good Leader and Coach. At the end of the day , a Sales Engineer ( And by the way any Sales related Jobs) need to have a massive energy and focus on self motivation..