We examine how lower-performing public school teachers respond to more frequent formative evaluations. A 2011 reform in Chile required teachers rated “basic” (the second-lowest category) to be re-evaluated after two years rather than four. Using nationwide administrative data on primary school teachers and students from 2005–2015, we show that the reform increased two-year re-evaluation rates by 58.9 percentage points. In a descriptive pre-post comparison, teachers who completed re-evaluation improved their evaluation scores by about one standard deviation. Yet, difference-in-differences estimates rule out effects on student achievement above 0.04 standard deviations, and we find no meaningful changes in student-reported teaching practices or caregiver-reported teacher caring. These results suggest that increasing the frequency of formative evaluations alone may be insufficient to remediate lower-performing teachers. They also caution against interpreting large gains in evaluation scores as sufficient evidence of improvements in teacher effectiveness.