Never Show Up Unannounced
Source: https://amazonaws.com
The Dutch are normally a very busy bunch, always having things to do and places to go. But they are very good at planning out their day to make sure they get everything done. Never shop up to their home or more so, their office, unannounced. Not only do they not like it, but they like to prefer to make plans in advance so they can fix you in their schedule like they do everything else.