Any situation where a new or elsewise unknown attribute breaks your code, binding is a big one. * Say you are joining two tables and one now has a conflicting/

Any situation where a new or elsewise unknown attribute breaks your code, binding is a big one. * Say you are joining two tables and one now has a conflicting/duplicate name, surprise, you now have broken code, it literally will not execute with ambiguous duplicate references. * By the same token, downstream views can break for the same/similar reason. * In some engines views are not going to actually include your columns until they are "refreshed"(SQL Server) so that one day that's out of band of your deployment your views will suddenly change. * Say you have a report with specific headers - tada, it's now got whatever people add to the table - and sourcing it can be a pain because its unclear where the source is in the query, requiring schema. * Performance expectations can change if the data type is much larger, up to the point of actually breaking the client or consuming tens of billions of times more resources.