When I started in contracting, I used to brand our company and work with "we have the very best service in the world, we'll do whatever you need to get things right."
Eventually, I got away from that. While I liked solving client challenges and working really hard to get a great ROI for clients, it didn't ring correctly to me. Something about how we said it, and how we did it, made things not quite right.
We always liked going the extra mile, and we offered a 100% guarantee on our work (sometimes even 100%+) to take the risk away from the client. We priced our services aggressively below market and looked to demonstrate results, in order to get repeat business. And indeed, we did -- it was just a few clients that provided the huge bulk of our revenue by coming back to us with orders for 5x and 10x larger than their original, and eventually getting to a trusted point where they'd ask for work over email and say "just bill me whatever, you guys have always been fair." That's a nice feeling.