Why the mobile phone is not dead?

Or perhaps it's more pertinent to ask "why there are plenty of sets available in the market?"
Even more precisely
"why can't I leave my phone?"

There may be a long list of reasons for why should not I leave my mobile phone but even more powerful reasons are coming up in favour of leaving this machine, throwing it to the stinking municipal vats.
Somehow, a small thread is preventing me from doing this, and it is hard to define the thread.

It is not
a. that I am fond of the set.
b. that I have developed some sort of humane attachment with the phone
c. that I have brilliant memories with the instrument, or the person at the other end of the instrument
d. that I want to get connected with everyone.

While I know some of the "it is not" but yet to find the dimension of "it is"