"Short-run subsidies for health products are common in poor countries. How do they affect long-run adoption? We present a model of technology adoption in which people learn about a technology's effectiveness by using it (or observing others using it) for some time, but people quit using it too...

It is often argued that cost-sharing -- charging a subsidized, positive price -- or a health product is necessary to avoid wasting resources on those who will not use or do not need the product. We explore this argument through a field experiment in Kenya, in which we randomized the price at...