The first solution is suboptimal, because it is possible that a reader R1 might have the lock, a writer W be waiting for the lock, and then a reader R2 requests access. It would be unfair for R2 to jump in immediately, ahead of W; if that happened often enough, W would starve. Instead, W should start as soon as possible. This is the motivation for the second readers-writers problem, in which the constraint is added that no writer, once added to the queue, shall be kept waiting longer than absolutely necessary. This is also called writers-preference.