Flowcharts have significant Limitations

Just two pathways both trying to go to the same two destinations become messy.  With three pathways, the messiness increases much more.  The connectors A, B, and C represent three pathways of some flowchart.  There is no way to connect B to the 'accept' process except by crossing the arrow from A to 'reject', The route from C to 'accept' is messier. 

The typical flowchart system also has difficulty representing subroutines, case statements, table lookups, and functions that are more complicated than FOR-NEXT and GOTO. 

Error Trapping in detail is another messy challenge for flowcharts.

Flowcharts should augment ideas or highlight algorithms

See FlowChart Symbols