You worked hard on the project, but your boss still pointed out a few deficiencies. A colleague at the office always snubs you. If you call your boss a perfectionist, or say your colleague is a snob, you have an external locus of control. If you analyse the situation, looking for your mistake, you have an internal locus of control. Although an internal locus of control makes for a positive attitude, it has certain disadvantages, too.
As explained by American psychologist Julian Rotter, people with an internal locus of control strongly feel that they are the masters of their destiny. Believing that you are solely responsible for the outcome of any situation leads to a strong desire to do anything and everything necessary to make sure it is positive. This makes people with an internal locus of control strive hard to allow no room for error. When there are others involved in completing a task, such people drive them too toward perfection. This causes others to perceive them as unreasonable.
People with an internal locus of control believe that it is their efforts that determine their life experiences. According to David A. Gershaw, Ph.D., a professor of psychology, when such people face failure, they experience a lot of guilt. They attribute the failure to something they did wrong, even refusing to consider that there may have been some external influencing factor. The next time they encounter a similar situation, such people get anxious about failing again, and go all out to ensure they succeed.
Although effort and ability are important, there are often factors beyond an individual's control that determine success. For example, if your boss criticises the way you rushed through a presentation, it may be that the time allotted to you was slashed at the last minute, making rushing necessary. If you have a strong internal locus of control, you will refuse to accept that this was a factor beyond your control, and instead, berate yourself for not being prepared with a shorter version of the presentation. When such situations occur repeatedly, it lowers your self-esteem and may lead to depression.
According to family and marriage therapist Dr. Jennifer B. Lagrotte, it is unhealthy to feel unduly responsible for others' happiness. People with an internal locus of control do this, and blame themselves when things don't go right. When there is an argument, they believe they must have said something to goad their partner. If their children suffer as a consequence of making a mistake, these people believe they could have done something to avoid it. A person's ability to introspect about her contribution to a problem is an appreciable quality, but overdoing it makes her susceptible to emotional blackmail by others.