Too much of anything can be bad. I'll counter that with:
High Standards
Pride is particularly useful when it helps us to have and maintain standards. I am proud of my professional abilities and will work hard to maintain them.
Pride can also be a unifying force in a group of people, such as when a team achieves a difficult challenge or lives up to its high standards. It has historically been used by leaders to encourage a depressed organization or country to feel good again.
In the negative sense, it can be used as a coercion, in the sense that you
must feel proud to belong to our group. It is often used by governments to enthuse a people towards war.
Hitler, for example, used it to rally the German nation after the defeat of the first world war and the subsequent ruin. How he then used it to persuade them into terrible acts is well documented. This is an approach used by more than one politician.
Achievement
When we achieve a
goal, we feel good about ourselves. A common part of this is feeling proud, where our self-respect and feelings of worth are boosted. In this way, our sense of
identity is increased.
Pride also can be in the achievement of ownership or position, for example when getting a longed-for a new car. There is a danger here of pride leading to looking down on others, although this is not necessarily so.
Pride is greater when we have had to work hard for something, as this makes the achievement more worthwhile.
Superiority
Pride in itself is not a bad thing and can be very useful for maintaining standards. However, it is named as one of the
Seven Deadly Sins in recognition of its shadow side, where it mainly about feeling superior to other people. This is often described as 'being prideful', as opposed to the more personal 'being proud'.
We often measure our achievement against that of others rather than our own previous performance. This is useful as a spur to determination. It is harmful when it makes us feel sadly inferior or arrogantly superior. It gets worse when we treat others badly either in spiteful revenge or prideful disdain.
The saying 'Pride goes before a fall' is an indication of how being prideful can lead to a self-importance that leads me to ignore risks (perhaps on the assumption that I am so superior the risks will not dare to happen to me).
Have reasonable pride yourself and beware of it going over the edge into a superiority complex. Also beware of developing an inferiority complex, which is also based in dysfunctional pride.
Pumping up the other person's pride such that they cannot see what you are really doing is a surprisingly common thing. How often do we flatter other people without really meaning what we say? When we flatter others, we usually have a persuasive ulterior motive.
http://changingminds.org/explanations/emotions/pride.htm