If the exhaust hose shows any cracks it means that the water has a chance to get into the wire and rust it out. The water can enter at one end and not look to bad BUT somewhere downstream (a low spot) the water will settle and do it's harm out of sight weakening the hose and the bond between the hose layers a bad thing. Also if the hose gets hot from lack of good water flow it can cause weakness and a delamination of layers.
Ten years is a good long life for an exhaust hose in salt water and maybe a bit longer in fresh water.
For safeties sake replace the hose if there are any doubts, worth the investment and labor
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Dave Neptune