If it's too easy for a child then their club should be moving them forward. If they don't like perfecting skills then gymnastics isn't the sport for them, because if will have to be done at some point.
I disagree with this notion and I think it causes us to lose many talented kids from the sport. Yes, it is important to perfect for, as a gymnast, but we must realise that this also comes with a level of maturity. Young kids in the sport at 6, 7, 8 years old are interested in learning cool skills not spending hours and hours on perfect form.
Prior to puberty is the best time to teach as many of the more advanced skills as possible kids are more flexible and learn these skills easier and faster, it is easier for coaches to spot. If a child spends a year on each level doing basic skills like straight jumps, then by the time they reach the level where they will be learning the harder skills, then they will be past the opportune developmental time.
You will lose the best kids from the sport because they are spending all their hours learning to do perfect walking in releve, straight jumps and kicks and must wait 5 years to learn that elusive back handspring.
Young kids need to fall in love with the sport and learn as much as they can. As kids get older the strength of their goals change and they are better able to focus on areas like perfecting form.
I am not saying that kids should be allowed to do messy skills and develop bad habits from an early age. But we need to be aware that there is a reason why such a higher percentage of US gymnasts reach the optional levels than Australian gymnasts.
The best kids for gymnastics are not the ones, who at 6, are prepared to spend hours learning to point their toes. The best kids for gymnastics are the ones who desperately want to learn to fly.