Sometimes I prefer not to draw a line, usually when the cable is running from one system to another (i.e. from one drawing to another). Common with room combines, or large centralised systems with lots of rooms running back to a single rack room. In these cases I wish to draw a line that terminates in the white space somewhere, with an arrow and a reference to where it can be picked up again (i.e. drawing number).
Eg. ---------> AVC_003
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Some others times I just want to avoid having a single cable winding its way through my entire drawing. In this case I might do:

Equipment ---------> (A)
and then somewhere else
(B) >---------- Equipment‌‌‌‌‌‌‌‌‌‌‌

Importantly - cable numbers/schedule being maintained through this. Obviously I can just draw whatever I want but then I need to manually manage the schedule and label printing.‌‌‌