Why is it so important for
medical doctors to be able to
use a microscope?

Doctors use microscopes to aid in their diagnoses. A microscope can be used to magnify cells and other specimens from a patient. Magnification of the specimen using a microscope helps a doctor to determine whether a sample is healthy or diseased. This will help determine the best course of action when treating the patient.
The benefits of microscopes to doctors are numerous. The ability to examine cells and tissues in greater detail can result in an earlier diagnosis and treatment that is tailored to the specific disease of the patient, as well as whether the cancer has spread to the neighbouring tissues.

Doctors use microscope so that they can see the very small cells which are not visible with a naked eye, but microscopes magnify and make them larger so that doctors can see it.