Poor data quality can have different sources:

• System inefficiencies. Neither your software or internal control system does not catch the poor data
• We are only humans.  Poor data a entered for sevaral reasons. Typos,  we enter data in wrong fields,  enter 0000000 in postal or telephone fields or just fill in as little as you are allowed to do

doCustomers set up our Data Quality Server to do intelligent continuous cleansing across databases with intelligent search to find customers or adresses.  In theory this will result in clean master database(s), but because of the system inefficencies and the human factor, some poor data is still found.  

We have a feature that can monitor the entries of data.  You can analyze why the poor data is entered, and then be corrected.  A mail is generated every day to a supervisor, that can analyse the result.  If it's human error the person who have entered wrong/insufficient data will be informed so they have a chance to improve their quality.  If it is system ineffiencies this will be corrected.  With this monitoring service the amount of poor data entered is drastically reduced in a short time span.