Clathrin-coated pits (CCPs) form during clathrin-mediated endocytosis (CME) with heterogeneous dynamics, with short-lived CCPs thought to arise from a failure to recruit cargo. It is unclear how CCP dynamics is regulated, but phosphoinositide (PI) levels, including those of PI(4,5)P2, are crucial. Because endocytosis is often perturbed in cancer, Sofia Merajver, Allen Liu and colleagues (Rosselli-Murai at al. 2018) now investigate the role of the tumour suppressor phosphatase and tensin homolog (PTEN), which converts PI(3,4,5)P3 to PI(4,5)P2 and is frequently mutated in human cancers. By using super-resolution imaging and automated tracking of CCPs in breast cancer cell lines, they show that activated EGFR and PTEN are recruited to short-lived CCPs and clathrin-coated structures, indicating that they act as signalling platforms. Deletion of PTEN in two model breast cancer cell lines resulted in a higher proportion of short-lived CCPs and a higher initiation density, which suggests that PTEN directly regulates CCP dynamics. Interestingly, PTEN-null cells exhibited an increase in CME efficiency, challenging the notion that short-lived CCPs are always abortive. Furthermore, the authors demonstrate that PTEN acts through its lipid phosphatase function, as the direct increase of PI(3,4,5)P3 in PTEN-null cells also led to an increase in short-lived CCPs. Thus, this work not only presents a new function for PTEN in regulating CCP dynamics, but also provides evidence for short-lived, signalling-capable CCPs.