has anyone made a good earnings with domain name parking and for how long

I would think that after some time users would stop visiting the domain name even if it was popular due to the fact that it is a parked domain.

Not sure what you mean by "good" earnings. I do alright with domain parking. However, my .in domains don't really earn much, and that seems to be a common experience.

Unless the domain was previously a website, normally the traffic to parked domains comes from people typing in the domain name "on spec" to see what is there. So, if someone is interested in Cars, they may just type in Cars.com rather than going to Google to search for it.

I have no idea how much repeat traffic there is. But people obviously do find parked pages useful, as the click through rate is very high. Think of a parked page kind of like an "Auto Trader" publication. People repeatedly get these publications even though they are just filled with ads. Often, a directory of what is for sale and where to get it is just what people want.

I find little success with parked domains. Usually I find that if someone is searching, they head back to google and search that way instead. The list of ads is frustrating to most searchers, in my experience.

Parked domains are more useful when you don't have anything else to do with the domain or you are willing to sell it off. Its better to have something out of nothing. But if you can monetize it without parking it , I would surely recommend you that.

I would not recommend parking for premium names but for mis-spelled domains, It might fetch atleast the yearly Fee plus some addtional change. Worth the pain and time only if you own more then 1000 domains....

Many people say that they earn good income with parked domains but i could not make it when i tried. High levels of traffic are required to make money, and if you have traffic, most likely you would be doing something else with it