Which phase of the cell cycle is the least common process of mitosis and what could be the reason?

In anaphase, the shortest stage of mitosis, the sister chromatids break apart, and the chromosomes begin moving to opposite ends of the cell. By the end of anaphase, the 2 halves of the cell have an equivalent collection of chromosomes. In telophase, 2 daughter nuclei form. The nuclear envelope beings to reappear.

i'm pretty sure it's spores

thinking it would be physical characteristics