It's true that sometimes cheating can be done online and not otb, and that is definitely a good thing about otb - but the advantage i find with online chess is that you can play a person of practically any rating, and at any time control.
Over-the-board or online chess - which is better?

The biggest advantage of on-line is the ability to play nearly as frequently as you want. The biggest advantage to OTB is the quality and intensity of the play.

The biggest advantage of on-line is the ability to play nearly as frequently as you want. The biggest advantage to OTB is the quality and intensity of the play.
I think being able to play frequently because of online chess has really helped improve my general game, so even after long breaks between otb games, the things you know are still fresh in your mind
OTB:
- more interactive
- more fun
- more genuine experience
- more real
- more honest (less likely to cheat)
CC:
- more boring
- more dishonest (more likely to cheat)
- slower
- more improvement
Just a few.