Why is it important that a drop of condensate be suspended from the thermometer during a distillation?

Distillation is the process of separation in which the volatile parts of a liquid mixture are separated by selective boiling and condensation. This process may lead to partial separation or complete separation. Distillation is employed for a considerable number of commercial processes such as the production of alcohol, kerosene gasoline, etc. During a distillation, it is important that a drop of condensate be suspended from the thermometer because it allows steady distillation and a stable temperature.