Telco tactics to stop switching due to number portability: price competition, quantity competition, bundling (new handsets), and all sorts of other sweeteners.
The sad part is that all one of them
could have built in switching costs easily, by creating consumer loyalty. It's a nice way to buy yourself some time when you're hit by strategy decay. Instead, their strategies and tactics were focused on opacity and confusion to extract maximum value from consumers - who are now very alienated and ready to switch, because all they care about is price - because that's the only source of value the network operators have created.