Why would he say that summarizing experience is unnecessary? Doesn't the point of writing a resume is to shorten one's entire career?

Native speaker’s answer
Rebecca
You're right. It is technically a summary! But, he's emphasizing the importance of it making it sound or appear good rather than just a list of things. It's about how the summary is delivered in a way that "sells" it! Ex: Don't just read the book to me, make it come alive! => Meaning to make it more interesting than just reading words on a page. Add emotion and depth. Ex: We're not writing an advert. We're selling a product! So what would make consumers interested in this?