
At the same time, indirect benefits usually end up outweighing those direct negatives. The fact that there are many sellers in the marketplace attracts the buyers to be there in the first place. And that is ultimately more valuable for the sellers, even if they have to sell at more efficient prices. The same is typically true on the buyer side.
It’s more complicated when we look at how same-side users interact. Most of the time, users on the same side subtract value directly from each other. For instance, core sellers on eBay create more competition for other sellers. More Uber passengers at rush hour mean surge pricing. Both are examples of negative direct same-side nfx.