становиться на мёртвый якорь

drop anchor; arrest one's advance; reach (come to) a dead end

- И потом, ведь он не растёт, - устало произнесла Вера Николаевна, - совершенно не движется вперёд... Стал на мёртвый якорь. (Ю. Герман, Я отвечаю за всё) — 'And then, you know, intellectually he's come to a full stop,' she said wearily. 'He doesn't strive ahead at all. He has arrested his advance. He has dropped anchor.'