Jogs are small loops drawn when two connectors intersect visually
but are otherwise unrelated. The jog helps to make it clear that
the two connectors are independent and that one simply crosses the
other without any kind of interaction.
Jogs can be enabled and their size can be adjusted from the
Connectors tab of the Diagram Properties dialog box.
Other notes about jogs:
The loop is always drawn on the top
or right of the connector regardless of the direction of the
connector.
Jogs on one connector must be
separated by enough distance to permit some spacing between each
jog. If a connector overlaps multiple other connectors that are
spaced too closely together, some jogs may be omitted.