Getting a lot of benefit for a lot of people for not so much money isn't particularly difficult. In the chart on the right, for example, (a) represents the cost of good signage at the airport, or clearly written directions on the prescription bottle or a bit of training for your staff. It pays off. Pay a little bit and you help a lot of people to avoid hassles. The utility per person isn't huge, but you can help a lot of people at once.
(b) is the higher cost of a bit of direct intervention. This is the cost of a call center or a toll free number or an information desk. You're paying more, you're helping fewer people, but you're helping them a lot.
(c) is where it gets nuts. (c) is where we are expected to spare no expense, where the CEO has to get involved because it's a journalist who's upset, or where we're busy airlifting a new unit out to a super angry customer. The cost is very high, the systems fall apart and only one person benefits.
Of course, if you're that one person, you think it's not only fair, but appropriate and right.
This "spare no expense" mantra is extremely difficult to avoid, because in any given situation, when the resources are available, your inclination is to say, "make the problem go away, spend the money!"
It's certainly possible to build a brand without going to (c) (witness the way Google almost never gets embroiled in special cases or even answers the phone–I know that they're certainly not eager to fix my imap problems), but once you've trained your customers that (c) is an option, it's awfully hard to scale back.
The reason we get trapped by (c) is that, "I'm doing the best I can" is always much easier than, "we need to be disciplined and help more people, even if that means that some special cases will fall through the cracks. The internet makes this even more difficult because people who fall through the cracks are able to amplify their complaints ever louder.
The way around it, I think, is to set expectations early and often. If you're going to give me your phone number, you better answer it. If you're going to offer a warranty, you better honor it. If you position yourself as a company with real people eager to make every single person happy–you better deliver.
No matter what, you should decide. In advance. How much do you want to spend on ad hoc emergencies, how much do you want to reserve on design and helping the masses improve their experience?