[CholeraJoe]

I’ve owned Labs for years and have seen them take on bigger dogs and even aggressive horses to protect children and adults. They are so eager to please that they often don’t realize their own limits and will keep going to the point of exhaustion sometimes.

[AnAmericanMother]

I have to watch my "little Lab" - who is now taller than her big sister - because she will retrieve until she falls over in exhaustion if you let her. Ears straight up, eyes bugging out, hair up on her back, inflated donut of hair on her tail, front feet dancing and hind end just barely staying in 'sit'. The dog is completely nuts. Brave as a lion, too - not afraid of live mallards, guns, flooded timber . . .

Eager to please - driven to retrieve.

Now my older Lab has some sense. If you send her on one retrieve too many, she will trot back to 'heel', deliver the bird, and then lie down and flip over on her back. "O.K., Boss, I'm done!"