Why take a private bus over a private ferry?

Busses leaves more often and starts, stops and travel much faster than ferry.

Do they? From the original reply:

>Surely this bridge will make it faster than the 1 hour ferry ride that leaves from 2 ferry piers in the middle of the city every 15 minutes or so all day and night. Unfortunately this isn't the case. The buses across the bridge from Hong Kong leave from the airport and take 40 minutes. You'll have to take another bus from the airport to the city at the cost of another 45 to 60 minutes.

The article itself says "Ferries usually depart every one to two hours."

If you are going to the HK airport from the Shekou port in mainland China, the ferry requires you to arrive something like 3 hours ahead of your flight, even though the ferry ride itself if only 30-40 minutes. I assume a bus wouldn't dictate your schedule in that way.