^ This can definitely be the case in a multi-producer/multi-consumer (MPMC) scenario if CAS is involved with loops. Great care has to be taken when writing MPMC data structures without locks that are more performant then lock equivalents; they are far more complex. I think it should be called out that it seems most (if not all) of the data structures provided are single producer/consumer which generally always have much simpler designs (and limitations of use) then MPMC.