It's a very good question, though. Dogs only recently became our couch adornments (I mean, other than the toy breeds, whose whole point is to be couch adornments). Pretty much every breed was created for a purpose, some more specific than others. It's worth looking at the history of your breed, and considering your expectations of your dog, and how their lives go.
The Doberman was created and bred to be a personal protection dog. Arguably, the Doberman today is not what the breed was fifty years ago, or a hundred. There's even, in some cases, a clera difference in the drive possessed by show and working line Dobermans. Dobermans have been softened, made more personable. They're not really "one man dogs" anymore (though I guess you wouldn't know that at my house...Elka listens...sometimes....to people other than me. She also sometimes doesn't listen to me, if she thinks she can get away with it. I tend not to allow that.) I've heard (and related) the anecdote that Ferry v. Rauhfelson of Giralda would not let the judge at Westminster touch him when he was at the show in the 30's. I've also heard that a Doberman in the 70's bit a judge, and it was after that the softening of the temperament was worked on. Now they're comfortable on our couches, trustable with friends and family, and happily eating pizza when offered.
If Elka could be said to have work, it's as my service dog. I have not rigorously trained her for public access; frankly, I didn't anticipate the need. Sometimes, my migraines are worse than others. The fact that I'm in the process of kicking my soda habit (Day 17!) has really exacerbated my headaches lately. Detoxing from aspartame and sugar and all that other stuff (I'd switched to diet, you see, but then tried to go back to regular. And then wondered what it was I was playing at and stopped drinking it altogether) is not pleasant, and for the first week resulted in headaches that painkillers wouldn't actually do anything about. Caffeine on its own didn't help with those either (tea and coffee are still on the table, you see), and so poor Elka was telling me, clearly, "Hey, you're kind of in trouble here". And I was replying "Yes, I know, but we just have to wait it out."
I'm feeling much better now, and so Miss Elka is able to be off high alert. She's been able to return to her other jobs, which include taking empty plastic bottles to the kitchen. There's a five cent deposit in New York, you see, so we collect our cans and bottles to return when an amount that's worth the trouble has amassed. So, to Elka, empty bottles = treats (empty cans, too). She has on occasion mugged somebody for their full bottle and brought it to me; I had her bring it back to them. But, bottle returns are not personal protection. Am I selling my dog short? Between those two jobs, she seems content enough. She keeps mentally active in that way, and our physical activity tends to be more of the "walk and play" variety.
I've mused before on whether Elka would protect the house. Even as a puppy, on occasion, she's interposed herself between me and an oncomer. So, would she protect me? I don't know. The next time there's a WAE (working aptitude evaluation) near us, I intend to go. It's meant to be a test of instinct, and in theory, all Dobermans have the protection instinct.
So, thanks to the Terrierman for the food for thought. I don't have definitive answers, but I've enjoyed chewing on the question.