Question

Two planes that do not intersect are always never or sometimes skew

Answer 1

hmm?? well They could be skew lines, which mean they do not intersect AND are not parallel. If they dont intersect they will never intersect making them parallel. Does this help?

Answer 2

Two planes that do not intersect never skew

Explanation:

Planes either are parallel or perpendicular. There's no other position between planes in space.

If a Plane is not Parallel, eventually it's a perpendicular one. Hence Planes never Skew.

Lines do skew if they are from different and non-intersecting and planes, and these lines subsequently not coplanar.