Should I always get on a call before closing a client?

[Btaliat]

Freelancers that are dealing with high-profile clients can opt for a call. Most times call does what writing proposals cannot do. When you call, you are building trust with your clients. Call them, convince them with your authority and tone. You don't need too sound to be bragging but you need to be speaking with authority. Ensure that you are arguing and negotiating at your own point of strength. What do you think about this?