Edge computing on the Internet of Things (IoT) is an increasingly popular paradigm in which computation is moved closer to the data source (i.e., edge devices). Edge computing mitigates the overheads of cloud-based computing arising from increased response time, communication bandwidth, data security and privacy, energy consumption, etc. However, given the potentially stringent resource constraints and functional requirements of emerging IoT devices, edge computing must neither be over-or under-provisioned for its stated purpose. In this paper, we present an overview of the problem of right-provisioned IoT edge computing, wherein IoT devices are equipped with resources that are 'just enough,' even when 'just enough' may not be clearly defined at design time. We highlight a few research directions and key challenges that must be addressed to enable right-provisioned IoT edge computing.