Do you bend the rules for your own clients?

In another discussion about motivation and failures, @Mrnewbie recommended a video by Louis Rossmann.
Louis is an American independent repair technician, YouTuber, and right-to-repair activist.

The next video that played automatically was also from Louis, titled 'Do you bend the rules for high-paying clients?'.

I believe you guys understand what it's about.

I think everyone has encountered clients who wanted more than what we standardly offer.
And I understand that in most cases, we accommodate clients when they request something extra for the first and second time, but what if the situation repeats over and over again?

I also understand that many will respond with 'It depends', because indeed — it depends. It depends on the type of person the client is, it depends if they are one of our early clients, it depends on the amount they are paying us, and many other factors. But still, what is your opinion on this?

I'm no business guru, and I don't have years of business experience, but I've heard from others that clients you allow to bend you once, will try to bend you multiple times after that. And if others see that one person has bent you to fulfill their own desires, they, too, will try to bend you. So, if you bend one time, a cycle can begin where, in the end, we're the losers because we were too permissive.

Depends on the type of Rules.
Legal Rules - No.
Rules that we as a company are applying, sure, all the these rules can be translated to money.

I worked very hard and sacrificed a lot of business over it, but I believe that it helped and will keep helping me in the long run.

I do not bend anything for a client. I go above and beyond for clients, but I make sure to stay within the boundaries for my services.