Why does morphing through Shape Keys not work correctly and the object turns into a chaotic set of triangles?

Morphing through Shape Keys can sometimes work incorrectly and lead to object distortion for several reasons:

• Topology mismatch: All Shape Keys must have the same number of vertices and the same order. If the topology differs, morphing will result in chaotic deformations.
• Incorrect application of Shape Keys: If keys are not activated or the blend weights are set incorrectly, the result will be inaccurate.
• Normals and mesh issues: If normals are damaged or the mesh contains errors, the visualization of morphing may be distorted.

Example: if you created a Shape Key on a mesh, and then changed the number of vertices (for example, deleted or added), the vertices will not correspond to each other during morphing, and the object will turn into a set of triangles.