Minimum feature size. The problem is that we've reached a point where not all features scale down evenly. So while some transistors might be 2 nm on a new proc

Minimum feature size. The problem is that we've reached a point where not all features scale down evenly. So while some transistors might be 2 nm on a new process, others are largely unchanged from 3 or 5 nm. How much you get out of a new process is now highly dependent on how you design your chip and what you want it to do. This is why AMD is using multiple processes in a single CPU package these days. Some elements of their processors get little or no benefit from smaller nodes, so it's cheaper to make them on an older node.