with the best will in the world even if you do all the things that would make you a good breeder you can still struggle with somethings. its a harder decision to say no than it is to take the 'compliment' and say yes especially for men I've found who are more than happy to prove their dogs abilities without any thought to the breed at all. Thinking more of their own bits than the well being of their dog or future progeny.
My friend had a Weimaraner that at 9 months was doing fabulous and he had a woman approach him at a competition and butter him up for want of a better word, wonderful dog, fabulous looking I'd love to use him on my bitch blah blah blah... it actually turns out she went for any dog that hadn't been used before because she didn't have to pay a stud fee

Nothing to do with how lovely the dog was or wasn't. as it happens the dog later died of a heart attack at four years old but was thankfully never bred from.
Breeding if you do it right is costly, time consuming, fraught with problems and unknown issues with regard to genetics and health and its not just from the bitches point of view, the dog can also catch and become ill from anything the bitch has... then there are the temperment changes, if the bitch attacks your dog or harms him by dragging him around when they are tied, so many things can happen. It really isn't all plain sailing.
The other thing is that EVERYONE thinks a puppy is cute and beautiful. When ayla and bonnie were pups I took them along Brighton Seafront and could never get more than a few yards at a time. Wait till he's three and see if they still say how cute he is, although i have found small dogs keep their cuteness far longer than the larger breeds.