[patio11]

That is not technologically or organizationally impossible, but there are many reasons to prefer paying based on estimated rather than realized LTV. One reason is that many affiliates incur non-zero traffic acquisition costs immediately, or close to immediately, because they use AdWords or similar methods. (Or, alternatively, because their SEO enjoys being paid money on a regular basis. I certainly like getting my salary from the bingo business regardless of whether the business sells a lot or a little in a given month!)

eBay currently extends them money far in advance of eBay receiving it, with the understanding that if there is an upside eBay will get most of it. If eBay pays them only after eBay gets money, that will cause many of them to go cashflow negative, and since they are not billion dollar publicly listed companies with easy access to capital at low rates, that leads to the firm either failing or exiting the eBay relationship. Neither of these outcomes benefit eBay.

There are numerous other risks this exposes affiliates to -- eBay retroactively changes the rules, eBay becomes unable to pay out the money, eBay has extrinsic changes in their business which lower payments after affiliates have incurred upfront costs sending them traffic, etc. All of these risks make eBay a less attractive partner to do business with.

You can't always have everything you want. There is a tradeoff here: eBay will pay you substantial amounts of money, up front, absorbing most of the financing and execution risks. However, in return for this, you agree to having your business relationship governed by what will appear to be black magic.