The point is that absent some coercive end-game to force compliance, there is no such thing, really, as either inside or outside obligations.
Most international relations, especially between friendly powers, don't rely on coercion or threat. The Council of Europe States signed up for a reason to that organization including the ECHR for a reason; no other country forced any one of them to obligate itself to the Convention and ECHR. The eastern European States, for example, signed up in the years after the fall of the Warsaw Pact and Communism to help develop their democratic processes and human rights practices after a long time of neglect. Italy has sometimes been slow to follow ECHR rulings, but that may be due to the complexities of Italian politics and a tendency for some decisions to be delayed as long as possible.