Root position or rotation are controlled by curves error on re activating game object!

Hi, I have a GameObject "Enemy" with animator and BoxCollider2d components, and 2 Sprites as children. The animation enables one of the 2 sprites every frame to create walking animation.

In the script the Enemy is made to move around the screen- (Transform.position and rotation are modified).

It works as expected.

But when I disable the Enemy and re-enable it again on the inspector while in Play, I get this error in the animator component: "Root position or rotation are controlled by curves" and the rotations of the enemy from the script stop working.

So to debug this I tried checking "Apply root motion" checkbox. Now everything seems to be working normally.

I know what root motion is, but my question is why does it work the first time even if "Apply root motion" is disabled? And why it fails if I re-enable it with same settings?