No you're not a bad pet owner for leaving your dog alone for 10 hours.
A dog will be fine left alone for 10 hours and in fact I've had to leave a dog home alone for 2 days once but I made sure the dog had plenty of water and food and he was just fine without me.
I didn't have anyone to take care of him so I had no other choice but to leave him alone while I went on a 2 day trip for my job.
I just made sure that he had plenty of food and water and he was able to go outside to potty into my privacy fenced in yard that has a fence tall enough to not jump and he never digs holes under the fence but I did have a neighbor keep a check on him from outside and made sure that he went inside but the neighbor was unable to fully take care of him because he's busy as well.