What is the major appeal to site flipping?

In the last half year or so (as far as I've noticed anyway), it seems like site flipping has really taken off. Why?

When I break it down to the fundamentals (as I understand them anyway), there seems to be some logic issues behind this practice.

Basically, you are selling a product, that you've created. You create a website, and then you sell it. Easy enough.

The more work you put into said site, the more you can charge, seems pretty basic.

But ultimately, due to the large number of site flippers, most people want to buy websites with established traffic, and established income. That also makes sense, I won't go buy a car if I can't check the maintenance records and look under the hood.

That's also where it gets weird to me. You are essentially creating an income stream, and then selling that stream for income (odd in and of itself). You expect to get 6-20 times your monthly income from that site, as it is a system, and doesn't have a set value.

My question is, if you can do something like that with any kind of regularity, why wouldn't you continuously do it?

I've sold several sites in the past. One of which garnered almost $140,000, and several more in the mid 5 figure range. I know that for me, selling the sites took a fair amount of effort, and time. I sell sites because I no longer have the want to maintain them, or because I need quick capital. I have never created a site with the intent to sell it.

To me it seems as though people are greedy, and will do anything for a quick payday, or perhaps are lazy, and refuse to see a project out to its full potential.

So what is the big deal behind site flipping? Sounds to me like anyone with this ability would be wasting it by selling the site, when you could easily outsource the workload and maintain the site, or outsource the method to getting the sites profitable, and start mass producing.

Any insight?