[Jtsummers]

If you don't control the network, though, it remains a risk. Whoever you partner with can renegotiate the terms later or back out of a contract depending on the exit terms (may cost them, but may be worth it for what they can get from Google).

This is the problem of the tenant, the renter. The landlord can change the terms and eat into your profits. At some point it's not worth dealing with them, but it's not always easy to leave.

[paulddraper]

But renters don't have market share.

If you're Amazon (Dropbox), you have a strong position to negotiate better shipping (network) rates from FedEx and UPS (ISPs).

[tomrod]

Depending on how many companies you negotiate with (monopoly vs. monopsony).

[Jtsummers]

And whether they’re competitors with each other. ISPs are largely regional monopolies so you can’t play them off each other as easily. They have the stronger bargaining position. Certainly stronger than Dropbox (people don’t buy internet service for Dropbox alone).