How does USDT make money?

Could you explain to me how USDT generates revenue? As a cryptocurrency enthusiast, I've been hearing a lot about it lately, but I'm still unclear on its exact profit model. I understand that USDT is pegged to the US dollar, but what's the mechanism behind its value retention and how does it generate income for its issuers? Is it through transaction fees, interest on deposits, or some other means? I'd appreciate it if you could break it down for me in a simple and understandable way.