I think, if a pod doesn't have any tolerations, we don't prefer node without taints to the one which has taints in https://github.com/kubernetes/kubernetes/blob/master/pkg/scheduler/algorithm/priorities/taint_toleration.go#L29, so there is no point in testing that particular functionality. The side effect of the above is, since we're going round-robin in every scheduling cycle sometimes we're choosing first node and in the next cycle we'd move onto next node(where taints are not being applied), so it's causing problem unnecessarily