The telicity behavior of degree achievements has been a puzzling problem to many linguists. The most successful and currently standard theory (Kennedy & Levin 2008) treats them as degree expressions lexicalizing different types of scales, which in turn influence the resulting evaluative or non-evaluative interpretation. While it may account for English, this theory does not hold up cross-linguistically. We challenge the scalar theory with new Slavic data and show that verbal prefixes influence the (non-)evaluative interpretation of degree achievements more than their underlying scales do. This proposal is formalised as an addition of two type shifters, morphosyntactically realised as prefixes, which, in result, have an evaluative/non-evaluative effect on the given degree achievement.