Well, there's a TON of reasons. I suppose the reasons I love dogs so much is because of they're outstanding loyalty and unconditional love. They could and would do anything for you, without hesitation.
They become like family.
I just lost my dog, and tbh, I would give ANYTHING to have him back. I regret thinking about all the times I hated feeding him as he got older- I had to hand feed him stinky canned food! I thought he took up so much valuble time, but now, I just have empty, wasted time :(
I don't know if you have a dog, but someday I think you will come to think the same thing I do. Maybe not.
Sorry for like, trauma dumping this week XD