As result we see a tendency of the boat beam growing wider and ballast ratio growing smaller. Now initial stability doesn't matter anymore. Shown below are two stability curves that demonstrate quite graphically how stability affect seaworthiness. The top one belongs to a seaworthy boat with good ballast ratio. Even when knocked down she would almost immediately turn into upright position with a very little push by wind and waves.
Bottom curve belong to a wide boat with plenty of initial stability but low ballast ratio.
When capsized she would require much more work by wind and waves to return her into normal position and could float upside down for considerable time. The single most important point on the curve is degree of vanishing positive stability which shows at what heel angle boat loses ability to self-righting. If knocked by a big wave she heels past this point, she enters the frightening area of negative stability . Any boat would float upside down until she's hit by another wave that helps her to complete full 360 degree turn. Some boats, those with narrow beam on deck and sufficient ballast do it instantaneously.