For Centuries people have been trying to "build a better dog". Ever since the domestication of the first canines, humans have been refining the dog to specific roles in our lives.
Every breed established and accepted today was created through selective crossbreeding - breeding two dogs that had desired traits with the hopes of producing in the offspring the best qualities - until definite trends were established and groups (based on a dogs abilities) and breeds (based on a dogs characteristics and appearance) were developed.
The AKC has ranked dogs according to popularity in North America. The Labrador Retriever heads the list at first place, with Golden Retriever ranked 4th and the Poodle ranked 5th out of 148 breeds. In his book "The Intelligence of Dogs" Stanley Coren ranks 79 dog breeds in order of intelligence. Poodles scored 2nd, Golden Retrievers were 4th and Labrador Retriever ranked 7th.
The Poodle has long been appreciated for it's beautiful curly coat with it's nonshedding and hypoallergenic qualities. Retrievers are people orientated, gentle, loving and calm. Both breeds are intelligent, easily trained, love water, retrieving and hunting.
Retrievers though, shed heavily. A trait that has become more undesirable over time for indoor pets. They are also not compatible for people with allergies.
Therefore the Goldendoodle and the Labradoodle became an instant success. Who wouldn't want a pet that melded the wonderful qualities of the retrievers with the fines skills and coat of a Poodle?