Well, 4 operators and 12 MVNOs ... not bad, but not still good.
5 of them are simply tariff plans with a different brand (
MTV Mobile, Telepass Mobile, A-Mobile, Digitel and Fenacom). Then a lot of difficulties: BT is a postpaid offer for "business customers", MTV needs to buy an handset (excet Tim customers), no MNP Wind<->A-Mobile/Telepass, etc. etc