What went wrong here?

[alanqning]

I spun out on a Boxster test drive accelerating slightly in a left turn from a stop in rain, all this in the middle of downtown Chicago and ending up backwards.

I knew about apexes, when to slow down and accelerate but was still surprised I broke traction. Never drove a Mid Rear engine before though, I thought they would have more traction in the rear due to the weight being there.