Can two wavefronts cross each other?
A wavefront is an imaginary surface that is formed from the collection of points that are all in the same phase.
The characteristics include:
If two wavefronts intersect, then at the point of intersection there will be two directions for the propagation of the wave which is not possible.
Therefore two wavefronts cannot cross each other as all the rays would take a similar time to travel between the successive ones.