Turning quickly at a roundabout or around a corner could increase the risk of having an accident in poor road conditions or from sudden actions by other drivers. DriveScore measures when you turn or go around corners in units of gravitational acceleration (G-force or lateral Gs).
We'll consider something as 'hard cornering' if you've turned more than 0.42 lateral Gs. This could happen by going around a roundabout or turning a corner quickly. We measure it in this way as a normal car could lose grip when going around a corner as low as 0.5G (if the surface is wet).
It's best to stay below 0.42G (G-force or lateral Gs) when turning corners as a habit of safety. Road conditions and other drivers can be unpredictable, so turning slowly gives you more chance to deal with the unexpected.