The concepts and terminology get in the way. People easily become confused about such ideas as efficiency and effectiveness when they try to apply them in practice. Not only that but the terms used, such as inputs, processes, outputs and outcomes (and higher order outcomes) are applied inconsistently, both by managers in practice and in some of the published literature on performance evaluation.

When people identify an area for attention or improvement they can usually come up with a list of things to do to put it right. Generally speaking, however, people find it much harder to think about the aims and objectives underlying what they are trying to do (that is, what they are trying to achieve by providing services). Unfortunately, this focus on aims is necessary: we need to be very clear about what we are trying to achieve if we want to be able to tell whether we have succeeded. Since people are usually more comfortable with organizing and running activities, their focus on impact often gets fuzzy – when this happens we slide off into identifying process performance indicators (or ‘tick off when done’ indicators). These tell us whether things on the list have been done, but they don't tell us whether they were worth doing, or indeed whether they have had any effect.