I'm sure everyone can recall a job where their emotions were disregarded and remember it as an awful experience. It is extremely difficult to work while being treated badly. Alternatively, if a manager cannot handle their own emotions, this could create a potentially uncomfortable and unpleasant working environment. Especially if a manager or business owner cannot control their anger or handle their personal problems, this leads to mistreating employees.
This is surprisingly common in many jobs. A boss who has a bad day and feels like it is alright to take it out on his employees.
There is a model known as the ability-based that attempts to help define emotional intelligence. This model has four parts: perceiving emotion, using emotion, understanding emotion, and managing emotion. This model, however, has received a lot of criticism when it comes to its validity in the actual work place. Despite this criticism, it is still widely known and serves as a guide to many.
Bradberry, Travis and Greaves, Jean. (2009). "Emotional Intelligence 2.0". San Francisco: Publishers Group West.