So many types of paint so much to talk about...
No that is not true that Candy Colors won't last long. Obviously the first paint job ever placed on the bare metal should last long if the quality and work was done professionaly. It's all about the prepping it'll depend on how you take care of your paint job and how the paint job process is applied. If you didn't let the paint cure obviously you'll have a crapped out paint job in the long run. To sum up all the complicating factors its mainly depends on the quality of work being done and how you take care of your car
If you're going for a color change go to a shop that backs up their work that provides you with insurance or warranty of some sort so you don't need to feel they have crappy work. And if something within the paint itself gets screwed then you can blame them.
The only thing that won't make a Candy Color last long is if you get a deep candy color that requires many stages to paint and if you get a rock chip it's a pain in the ass to repair. Your statement "won't last long" fits in that situation and the "stock" color being a single stage will be hell of a lot easier to color match instead of shooting a whole car over to get the multiple stages to match that candy color.
Just please don't try to go with a Candy Color and hit up a 1 day paint shop the quality will not last long. I could probably hear people telling you "Candy Color won't last long" because it is pricey to maintain the balance within the stages and the conditions the paint job may go through if you get road debris damage. A true Candy Color is beautiul, free from flaws, and in high color quality. It is a very demanding to take care of when it comes to maintaining and requires a lot of attention to detail. I reccomend getting a clear bra if you're paint job becomes an investment. Get a clear bra or shoot a clear gel on area's that have high impact zones to rid some of the road damage. You don't want to be re-painting your car 24/7
