What you say is true for a certain type of users and a certain type of business, but not for all the users and uses that a Heroku app might have - big companies, small companies, consumer sites, internal tools, iOS apps, etc. You have to assume a variety of use cases here, because that's kind of the whole point of a platform business.
What about when the user is your boss? "Hey, did you fuck this up?" is not a question people want to hear all day.
Or when it's an internal tool, and your users are a whole bunch of people who work with you?
Or when the site that went down is the system you use to invoice your consulting client, and they know you wrote it? Would you be anticipating repeat business?
A tiny portion of consideration for other people when you write your error messages can save those other people a great deal of stress. 37Signals wrote a book on that in around 2005 or so:
It's short but it's good. (twss)
I think people are getting way too angry about this, and geeks get awfully weird (and often oddly furious) whenever you suggest employing simple social graces, but I also think it's indisputable that OP is absolutely right.
And to be fair, I didn't have any apps hosted on Heroku when this took place, so that might even be the reason why I think people are getting too angry about this. Maybe they're right to be mad.
"If you had a setup with a hosted machine at Rackspace and the power goes out, you don't expect a custom error. So why would you expect one from Heroku?"
Because Heroku's not Rackspace. It's a service, and one thing people like from a service business is good service.
I like Heroku, it's awesome, but asking them to take responsibility for their downtime is a reasonable request.
"Submit Now: Designing Persuasive Web Sites" by Andrew Chak (2003)
• Similar to "Don't Make me Think", but focuses more on personal interaction & choices more than layout.
"Defensive Design for the Web: How to improve error messages, help, forms, and other crisis points" by 37 Signals (2004)
• Error management (not just 404s) is one of the most overlooked UI portions of a web project and are often left up to the developers to "figure out".
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