I expect the cost to Zipcar is that they rely on oversubscription and underuse, a bit like porn sites.
I guess it depends who you are but wouldn't porn sites be overuse and undersubscription?
No. As I understand it, porn sites depend on recurring subscriptions that people forget to cancel. If it were overuse and undersubscription, they wouldn't be profitable.
This is true. As I said in the porn thread, I used to work at a large porn company. One time we had about 3 weeks of significant intermittent downtime, due to a really bad server migration.
I suggested that we send out an email to the subscribers offering a one-month credit if they wanted it, and the management looked at me like I was crazy. When I asked why, they explained that if we sent an email like that out, it would remind the members to cancel their subscriptions.
That was a big part of my inspiration to create the "iTunes Store for porn" application.
If you stop paying rent, they don't just kick you out, they try to get the missed payments back too.
The apartment analogy is a very poor one for this argument, especially when one would theoretically continue living in an apartment while they stopped paying for it.
This author, Fred Stutzman, clearly stated he quit using the service sometime between "last year"(2008) and March of the following year, 2009.
For me, it's more of like magazine subscription. If you don't renew, they can just stop sending you magazines.
With apartment renting, you continue to use the service/product. If you stop paying your rent, they need to kick you out of your apartment.
If you don't renew, what is the cost for Zipcar since you can't avail of the service anyway?