In my opinion it's destroying Ukraine as a country. Even if it takes years he's ready to keep this thing going until our economy collapses.
I mean, you're right, Russia hasn't succeeded in its goals. But if we take a look at Ukraine which will start to struggle economically in near future [1] you can change your opinion.
[1] - https://www.economist.com/europe/it-will-be-hard-for-ukraine...