As seen in the output below from "Practice lab of Node Affinity", both master &a . . .

Mudit:
As seen in the output below from “Practice lab of Node Affinity”, both master & work nodes, do not have any “Taint”. But every time I schedule a nginx pod using ‘kubectl run…’ command, the Pods always get scheduled on node01 and not on master/controlplane node. Why is it so?
Note: No NodeSelectors or Affinity rules are set in this cluster yet.

root@controlplane:~# k describe nodes  node01  |grep -i taint
Taints:             <none>
root@controlplane:~# k describe nodes  controlplane  |grep -i taint
Taints:             <none>
root@controlplane:~# k get nodes
NAME           STATUS   ROLES                  AGE   VERSION
controlplane   Ready    control-plane,master   29m   v1.20.0
node01         Ready    <none>                 28m   v1.20.0
root@controlplane:~# 

Vijin Palazhi:
scheduler tries to place the pods on the node that it is best suited at that time. If you add more pods / scale up deployments, eventually some pods will also be scheduled on the controlplane.

Mudit:
thanks @Vijin Palazhi