I love advertisement and especially the posters you cross in the public transports.
I really enjoyed the current campaign of Vodafone UK :
and this one
So did you get the message? I DIDN’T!
Vodafone guarantees it works (ad #1) but Vodafone has a service that helps make it work at home (ad #2) (because it doesn’t). So what do you assume? You assume Vodafone service just DOESN’T WORK or at least they cannot guarantee it does!
The only sure thing is they should change quickly their agency and the communication team that drives them.