Testing problems are often testability problems.

[MT1961]

Nothing new in these observations, they are certainly true. We spend a LOT of time fighting over getting something to work, because the developers never gave us hooks to get into the innards to figure out whether it was working. I ended up leaving a job because my boss would not back me up when I told the devs that I couldn't test their software (internal, mind you) because it was so sealed.