Even though adhesion events occur more rarely in the pristine flow tests, they have important consequences, and may eventually lead to clog formation. In pristine flow tests, video evidence suggests that there are instances in wider parts of the device (w c /d p > 5) where a discontinuous clog can be initiated due to the adhesion of a single particle to the channel (see Video S6 in SI). In the video, five individual particles can be seen sticking to the device, each in a different channel. However, individually adhered particles may or may not result in a clog. In the video, only one of the five leads to a complete clog. Further, more than two minutes elapses between the first individual particle deposits and the time at which the channel is completely clogged. Often, particles simply flow past a stuck particle. There are even instances where a downstream clog can grow over and past particles already deposited within a channel (see Video S7 in SI).