There are only so many ways you can communicate with a customer, and here they are:

Face-to-face: the most effective communication method. You get to pick up body language and understand context. Also, it’s the fastest way to communicate.; there’s little room for miscommunication in F2F meetings.

Video: second best to F2F, but it can be beneficial. Context and nuance do require a bit more work here.

Phone: not bad if you’re talking with someone you know. But obviously, a lot of nuance and context goes missing.

Email: a pretty horrible channel when trying to convince someone of something, or exchange ideas. But it’s fine as a utility tool, e.g. "Are we still on for tomorrow at 10am at Starbucks. Yes?"

Text: seriously? It’s best used as a utility tool only. (See the "Email" example.)

Smoke signals: pretty much on the same level as emailing and texting if you’re trying to impact behavior and influence thinking.

Good selling requires changing perceptions, explaining complex and nuanced concepts (and product features), and solving problems. Of all the modes above, you know which one is best.