Dropbox' strategy is becoming the permanent storage for all of our data. But its business model (charging by GBs) discourages the user from using Dropbox for all of their files. For many users, the business model necessarily limits their assimilation of the product.

Flickr wants to be the place where people discover and share amazing photos. But they charge their most engaged users extra money for storage, discouraging them from adding the very content which makes the product valuable to new users.

Metered billing is like a usage tax. Taxes discourage behaviors. Don't discourage your users from taking the very actions which make your product valuable.

Thoughtful post Fred, thank you.