Buffer Bottlenecks
Assume that the system has a single buffer and is performing both input and output on one character at a time, alternatively.
In this case, the sector containing the character to be read is constantly over-written by the sector containing the spot where the character will be written, and vice-versa.
In such a case, the system needs more than 1 buffer: at least, one for input and the other one for output.
Moving data to or from disk is very slow and programs may become I/O Bound ==> Find better strategies to avoid this problem.