All implicit couplings seem convenient when first introduced, but later become reasons that the code cannot be easily diagnosed, repaired, or extended…
How often do we hear developers saying that they would love to make an improvement to the code structure, but that it would take too long, cost too much, and risk too much? Typically, the programmer sent to resolve the problem must write the code that the original author avoided. Unfairly, the original author may be initially credited with quick turnaround, when in reality he did an incomplete job that his colleagues must finish for him.
(src: http://pragprog.com/magazines/2011-01/code-coupling)
