Have you ever worked with a tester?
I've done some unit (aka alpha) testing before, and I've defined the occasional test script, but I've never done the job in a mainstream way.
I attended our project kick-off meeting a few weeks back and following on from my presentation was a 15-minute slot for our test manager to describe the test strategy, environments, etc. He's an enthusiastic guy with a great deal of experience in testing. He's made a career of it. In fact one of the points he made during his presentation was that the people he'd be recruiting on to the test team would all be ISEB (I think he said) certified, and he was very proud that there was a testing career path defined now in his part of the organisation.
Listening to him speak about testing with a glint in his eye made me realise (yet again) how different people are. I could no more get excited about testing than fly to the moon by flapping my arms (even if the physics didn't prevent me, before you get all scientific and start going on about vacuums and such). But it's a good job someone can, because if we didn't have testers we wouldn't be able to deliver. It's back to the old arsehole scenario again. Some people are made for the job. Years ago I worked with a guy who looked on testing as a challenge. It was him against the developer and may the best man win. His goal? To break the system, any way he could. Fair means or foul. If there was a way in, he'd find it. Garbled inputs, unexpected fields in data, pulling out network cables mid-transaction, corrupt files on disk, malformed packets. You name it, he'd try it. And every time that system crashed, he'd chalk up another point on his side of the scoreboard.
But you know what? Even though he was just about the most hated person on the payroll as far as the developers were concerned, they had to admit a grudging respect for him. He was damned good at his job, and they had to raise their game to get their code drops past him and out to integration, which had a positive effect on the project overall.