It’s not a perfect analogy but if it were, it wouldn’t be an analogy! While the human user has more choice in selecting a marketplace than a cow, our goal as marketplace founders should be to be good enough at meeting the customer and user’s needs that both feel like they don’t have any choice but to use our platform.
Want to build your consumer brand with user-generated content? You might already feel like you have no choice but to use Instagram. Want to see how much money you can get for your used smartphone? You’d be mad not to at least try eBay. Want to sell it only to people in your local community? You really have to try hard not to list it on Gumtree.
There are competitors to each and in some cases, the competitors actually work better (for instance, in my experience Facebook Marketplace works better than Gumtree) but in each case the dominant marketplace operator has created the perception that a sensible user really has no other choice.
Part of that is massive marketing spend, part of it is being first in some cases, but a big part of it is in focusing on prioritising the needs of the customer early on. What problem would you rather fix: a marketplace with lots of listings, or a marketplace with no listings but lots of buyers?