If a guard dog is oversocialized can it lose its purpose as a guard dog?

Anonymous
Lets take the case of my friend's cousin and his dog, a large male Rottie. His store got robbed 3 times (once in late 2018 and twice in 2019) and his dog did nothing. He thought the robbers giving him biscuits were friends. One of the robbers took him for a short walk, then came back and left as if nothing happened.

The dog was been around lots of people (men, women, children and babies) another dogs and animals all his life, 24/7. However, it acts as if everyone wants to be his friend, indiscriminately. They are supposedly great guard dogs. Though, if it got raised into treating everyone as friends and never train to discriminate/guard can it lose its natural guarding instincts, purpose? Is it good to oversocialize a guard dog, esp if it's a powerful breed?
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+1 y
While it's great to have an easygoing, friendly dog... his dog is super naive and a couple times have invaded other dogs' spaces. A couple dogs backed away and found it uncomfortable when he approached too much, thinking they wanted to be his friends too.
If a guard dog is oversocialized can it lose its purpose as a guard dog?
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