Visually Key Performance Indicators (KPIs) need to be simple. Avoid the "fluff" and the temptation of creating flowery good looking graphics that don't convey meaning. KPIs are a management tool that (hopefully) are used by management. They should be designed to convey information visually and quickly so management can evaluate the impact on their operations at a glance. This visual dynamic will ensure problems and opportunities are identified and actioned quickly. Management really shouldn't be looking at performance images that take time to decipher and interpret. Management time, at best is in limited supply, so the easier information can be portrayed and interpreted the better.
All graphs have a purpose, to convey information simply and quickly, and with the right data mining amazing things and relationships of data can emerge. But in terms of business performance, simple line or bar charts offer, in most cases, a comprehensive analysis of what is trending, whether results are being achieved, and whether action needs to be taken.
So the old adage of "Keep it Simple Stupid" (KISS) certainly applies to Key Performance Indicators. Visual interpretation without interrogation, quickly and effectively is the key to unlocking effective management performance through Key Performance Indicators.