You could have gone with a simple prologue of Please be respectful. Instead your first reply contained no substance at all. You were doing nothing to actually help, such as getting them to clarify the problem. That's likely to rile up the customer even more. On top of that, your tone wasn't appropriate.
> I sincerely don't understand how that's controversial at all
There are gradations. If the customer were being truly offensive, that would be one thing, but in this case they're really just making themselves look like a petulant teenager.
I'd have rolled my eyes and got to work, knowing they'll probably behave better (and regret their silly outburst) once they know I'm taking them seriously.
If an employee sent a message with this level of rudeness, then sure, you'd want to have a word with them about their netiquette, but customers can't be held to the same standard.
> I'd have rolled my eyes and got to work, knowing they'll probably behave better (and regret their silly outburst) once they know I'm taking them seriously.
This is where I think you're mistaken. Customers and clients like this, once they see they've gotten you under their thumb, will be more than happy to continue exploiting you.
Remember Stavros was charging a small lifetime fee. Clients from hell will twist this and try to make you their personal developer for as long as possible.
You seem to think that Stav should be thankful for the opportunity to fix the particular bug, but who's to say he wouldn't have discovered and fixed it on his own time?
Customers can and should be held to the same standard. Otherwise you end up with shit customers.
> Customers and clients like this, once they see they've gotten you under their thumb, will be more than happy to continue exploiting you.
I'm not saying you're obligated to be a total pushover. You're certainly not obligated to agree to every feature-request, or even to every bug-fix request. I still don't think the way they handled the support request (such as it was) was appropriate.
> Stavros was charging a small lifetime fee. Clients from hell will twist this and try to make you their personal developer for as long as possible.
We don't have reason to believe this is what's happened here. I figure the customer was probably just frustrated and, yes, rather rude.
If you make the decision to sell a lifetime service, you take on some level of lifetime support obligation.
> You seem to think that Stav should be thankful for the opportunity to fix the particular bug, but who's to say he wouldn't have discovered and fixed it on his own time?
If handling their issue properly results in uncovering a bug, that's a good thing. I don't think it's of much consequence if you feel thankful.
The customer was still rude, sure. Does that outweigh the benefit of discovering a bug? I don't think it matters. The question is about offering good service and handling rude customers.
> Customers can and should be held to the same standard. Otherwise you end up with shit customers.
But you've already chosen to take their money in exchange for a lifetime service. It's not the same as declining to renew a contract.
If the customer is being outright abusive, that's reasonable grounds to decline to take on their support request. I'd draw the line somewhere above this sort of low-level rudeness though.
> I sincerely don't understand how that's controversial at all
There are gradations. If the customer were being truly offensive, that would be one thing, but in this case they're really just making themselves look like a petulant teenager.
I'd have rolled my eyes and got to work, knowing they'll probably behave better (and regret their silly outburst) once they know I'm taking them seriously.
If an employee sent a message with this level of rudeness, then sure, you'd want to have a word with them about their netiquette, but customers can't be held to the same standard.