The Dutch architecture is an interesting thing. The Netherlanders have many good architects but the traditional Dutch house does not give much scope for creativity. The traditional Dutch house is narrow and tall and quite often leaning sideways.
Like this house in Hoofddorp.
The reason for this problem that The Netherlanders have with true vertical is the foundation of the buildings. Lot of buildings are built on old seabeds where there are up to 100 meters of clay between the building and solid rock. To get semi solid foundation for the buildings The Netherlanders need to drive poles into the ground. They use wood below water level and concrete above water level. Current thinking is that about 40 meters is enough foundation for regular building.
Of course many of the buildings are really old so they've had plenty of time to settle down and start leaning a bit.