How open-ocean and coastal sea conditions differ

How is the middle of the ocean different from the edges?

Open-ocean waves can build larger without land interruption; coastal waters may break the swell but add rocks and much less room for error.

The open ocean tends to produce larger, longer-developed swells because land does not interrupt them. A capable ship and crew can often ride those swells, whereas coastal waters introduce rocks, shoals, and limited maneuvering room. The coast may look calmer, but the consequences of navigation or handling errors can be more immediate.