Causes
The most common cause of feature creep is the desire to provide the consumer with a more useful or desirable product, in order to increase sales or distribution. However, once the product reaches the point at which it does everything that it is designed to do, the manufacturer is left with the choice of adding unneeded functions, sometimes at the cost of efficiency, or sticking with the old version, at the cost of a perceived lack of improvement.
Another major cause of feature creep might be a compromise from a committee which decides to implement multiple, different viewpoints in the same product. Then, as more features are added to support each viewpoint, it might be necessary to have cross-conversion features between the multiple viewpoints, further complicating the total features.
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