Companionship and she is a Service Dog.
Over fifty years, we had Five Dobermans, all fantastic dogs, with proper training and lots of love.
This time, I chose a German Pinscher because I am too old to have ninety pounds slamming against my knees. I fell in love with GPs at a UKC Show around 1990 - decades before internet. There was no information whatsoever available on this wonderful breed. Copper came from Arizona with amazing breeding and excellent health.
I love her intelligence and especially her SPIRIT, and her desire to please!
My major concern in her training was how to control the GP high prey-drive. It was really easy. I smothered her with Love and POSITIVE discipline. Because she loves me SO much, and because she gets lots of praise, she'll do anything for me. Including calling her off chasing coyotes, which are afraid of her - she's quite ferocious with them, because she was taught coyotes are NOT dogs - they are BAD! So she wants to protect me from them.
Even though she barks as strangers approach HER house, her one fault is she is worthless as a guard dog - everyone is her Best Friend! Sometimes she does "sleep-overs" with the kids next door - she loves them too. Copper has been super-socialized at the Dog Park.
Copper has had three showers with me, and is an exceptionally CLEAN dog, with very little shedding. Some sources state GPs are yappy dogs. This is totally untrue with Copper - she only barks on command and when she is supposed to.
I never trained a Service Dog before, but somehow, she knows when she has her SD Vest on, it's time for serious work and paying attention. She is excellent with basic obedience, and can be controlled with hand signals, even off leash. She sits quietly while waiting, remains under the table in restaurants, and rides the Metro, elevators & escalators with me.
DO NOT get a GP if you've never had a dog before - they require experienced Owners, who know how to discipline dogs POSITIVELY!
====>NEVER yell at a GP - ignore the bad things which happen. When a GP does something correctly, praise them like they just won a Gold Medal at the Olympics. That's the kind of discipline they require.
Simultaneously, you must make a GP understand YOU are the Alpha Male in your Pack, so they don't try to get away with bad behavior. Then they will respect you for it and love you even more.
And in the GP info above, they NEVER get to be 77#! Wikipedia describes them more accurately - The German Pinscher is a medium-sized dog, weighing between 25–45 pounds and typically 17–20 inches at the shoulders.