Why people have Google Search completely wrong
julianyap.com
julianyap.com
Indirectly, Google et al must make search better, because otherwise we (the "product" being sold) do not come back ...
Secondly, I think Google, as most other companies out there, do not just focus their energies in one revenue stream (although it may be the biggest one) and do not create products for a single reason. So, thinking Google+ is just a way to make directed ads easier is oversimplifying things. That may be part of it, but not letting Facebook create a Walled Garden is another part, and create loyal users is another one.