Pat Dorsey is the former director of research at Morningstar. He has some very interesting contributions to the concept of moats, which he spells out in two of his great books, The Five Rules for Successful Stock Investing and The Little Book That Builds Wealth. You can also see my interview with Pat Dorsey at the following link, where he discusses topics like what IS and what is not a moat.
In this video with The Manual of Ideas, Pat Dorsey discusses how management makes decisions which can increase of decrease the moat. He discusses $AMZN $WMT $TGT $NOK $CSCO $GRMN $CTAS in particular.