In many networks minimizing delays from entry to exit is a major concern. In user-optimal routing, each user chooses a path to minimize delay from entry to exit, given the existing paths chosen by all other users. At equilibrium all users experience the same delay. This report describes single-server queuing networks in which adding servers or increasing the capacity of existing servers worsens the delay experienced by all users. Our findings are closely related to those of Korilis, Lazar, and Orda.