The potential for data to be corrupted and polluted increases as it gets passed through interfaces and contact points, and as it passes from process to process and from system to system. This makes data hard to keep clean/ Those of us in the data quality world often hammer at the point that getting the data right at source is the ideal for a high level of data quality. But not all data is correct or standardised at source. When the originator of that data, as much prone to data quality defects as the rest of us, can't decide on what form it takes, what chance for getting it right in your systems?
Read more in my blog post here.