When you realize NVMe turns your high performance 6 Gbps SATA ports off and you have to migrate 500GB of data from one SSD to another over 3gbps... and it gets slower once you consider that you as a software developer have millions of tiny files that take even longer to copy over. Oh yeah also your boot entry doesn't work so you have to fix that one up. Upgrading from 500GB to 2TB easily cost 4 hours plus letting it run overnight to avoid wasting time on the transfer.