The thing is, they just simply work. The lids fit, and are interchangeable. You can drop them on pavement (I have) with no notable damage. They keep coffee hot, and they keep cold drinks cold. They aren't the cheapest option out there, but my wife and I use our Yeti mugs every single day, so I'm willing to spend $30 on a tumbler that makes my life easier.

I play guitar, and according to my wife, I have too much gear: guitars, amps, pedals, etc. There is a guitar effect pedal company out there called Meris, and the secondary market is flooded with these pedals. The average user review includes something to this effect: "This might be the best sounding pedal I've ever played....but it's so maddeningly complicated I just can't see myself using it long term."

It's easy to recognize quality, but quality without ease of use is useless. Consider Amazon; it's not that they are the least expensive option that gets us to buy from them; it's that they make it so easy to buy from them that in many cases we don't even compare prices - because what's $3 savings really worth if I have to go out of my way to buy from the less expensive supplier?

Empathy is the key to building ease into our businesses. It is crucial to try to picture every interaction from the viewpoint of the client/prospect and do anything we can to ensure that the process feels easy to them. In an ideal world, the experience is so seamless that the client simply doesn't consider other options, because we make it so easy to do business with us. We will never go wrong by being empathetic toward our clients.