Lots and lots of knives are discontinued every year. For a healthy production company it's mostly due to a reallocation of resources to enable the launch of new products, not to bury a defective or potentially dangerous model. In the case of the Diskin Strobe, it was likely only a middling seller in a very broad product line that met the end of a decently profitable lifespan. A telling point is that its fixed-blade sibling, the Diskin Hunter, also appeared on Kershaw's discontinued list this year. Obviously no lockup safety issue arose with this model, yet it's discontinued all the same.
A comparable situation exists with Spyderco. Much like auto manufacturers, and much more so than Kai/Kershaw/ZT, Spyderco "freshens" old standbys all the time in the form of "sprint runs." To be sure, Spyderco discontinues a lot of models too, but like Kershaw, just to free up manufacturing capacity to introduce new designs. In fact, I can think of only two Spyderco models that arguably met an untimely demise due to design defects: the much loved but lock-wear prone full-size Tim Wegner C48 and that bold but ultimately weak effort, the C115 T-Mag. Just so there's no misunderstanding, I remain the proud owner of a pair of each.