"I don’t gain anything whit implementing IPv6, it only increases costs"

This argument is related to the (lack of a) IPv6 business case. It is assumed that the introduction of IPv6 will require extra investments. This will in most cases be true: at least someone has to determine the impact of the introduction of IPv6. But the costs can often be minimized by doing IPv6 investments concurrently with the introduction of new network devices and service platforms. As far as revenues are concerned: not be able to deliver IPv6 on time, may lead to missed opportunities, missing potential revenues.