A new study now says that feeling blue can actually help some people to focus, manage their time and better prioritise work.
On the contrary, researchers found being in a good mood may hamper time-keeping and organisational skills.
However, according to the study, this was only true for extroverts - while introverts ground to a halt when they felt gloomy.
The study, carried out by Tara McAuley, a psychology professor at the University of Waterloo, and Martyn S. Gabel, a PhD candidate; explored how 95 people cope with the demands and stresses daily, depending on their mood.
Researchers focused on emotional reactivity - the sensitivity, intensity and duration of emotional responses associated with mood.
These things are the defining factors that influence 'effective functioning' (or, abilities to carry out tasks).
They broke down the group into categories of emotional reactivity - high-reactive people and low-reactive people.
High-reactive individuals (i.e. extroverts) are people who have rapid, intense, and enduring emotional responses, while low-reactive people (introverts) are more relaxed.
In the research, extroverts performed better on executive function tasks when they were in a bad mood.
However, low-reactive people showed the opposite effect: their abilities would grind down to a halt when they were in a bad mood.