Related:

• 1) If a test installation functions perfectly, all subsequent systems will malfunction.
  2) Not until a program has been in production for at least six months will the most harmful error be discovered....
• Variables won't. -- Troutman's Programming Postulate #5
• Constants aren't. -- Troutman's Programming Postulate #4
• Troutman's Sixth Programming Postulate: Profanity is the one language all programmers know best.
• Profanity is the one language that all programmers know the syntax of.
  -- Troutman's Programming Postulate #6...
• A Batch Stream that can not be arranged in improper order will be.
  -- Troutman's Programming Postulate #3...
• Troutman's Fifth Programming Postulate: If the input editor has been designed to reject all bad input, an ingenious idiot will discover a method to get bad data past it.
• The most harmful error of any program will not be discovered until the program has been in production for at least six months.
  -- Troutman's Programming Postulate #2...
• Steinbach's Guideline for Systems Programming: Never test for an error condition you don't know how to handle.