in-: in, into
cept: derive from Latin "capere", meaning "take"
-ion: something of doing something
So inception means:
The state of taking something into the world.
It means "the state of incepting".
Evolution of usage
Since its state of taking itself into the world the company became bigger and bigger.
Since its state of incepting the company became bigger and bigger.
Since its inception the company became bigger and bigger.