Hire one tester for every two programmers

[nancylebov]

Top Five (Wrong) Reasons You Don't Have Testers

Besides, the whole point of letting "your customers" do the testing is that they find the bugs, and you fix them. Unfortunately, neither Netscape, nor any other company on earth, has the manpower to sift through bug reports from 2,000,000 customers and decide what's really important. When I reported bugs in Netscape 2.0, the bug reporting website repeatedly crashed and simply did not let me report a bug (which, of course, would have gone into a black hole anyway).

Link from KeithS at Making Light.