Interesting article on customer service:
https://hbr.org/2019/02/why-is-custo...its-profitable

The article states that customer service is bad because it is profitable. People still book with Marriott even with terrible customer service, so Marriott has no incentive to make improvements.

Also, a lot of companies outsource their email support. Usually, the employees are under high pressure, judged by their metrics. To keep their job, they aren't evaluated by their customer service quality, but by how "efficient" they are. Thus, spending even 10 minutes on a difficult case will put their job in jeopardy.