So far BeanUtils can cope with properties conforming to the Java Beans specification. In some situations it makes sense to relax this requirement and allow the detection of other forms of get and set methods as well.
For instance, fluent APIs have become popular. Here you have a set method which does not return void and thus violates the Java Beans specification. Objects using such an API cannot be dealt with by BeanUtils currently.
For reasons of backwards compatibility the current behavior should remain the default. But it would be cool if there was an option to set a custom introspection policy. The policy would be invoked during property discovery and can decide which properties to include or not.