Many fluorescent tube guides recommend replacing the bimetallic strip starter every time the tube is replaced; however, no one seems to provide a specific reason why it needs replacing. Presumably you could keep using the starter and only replace it when it no longer lights the tube – but perhaps there's a good reason why you shouldn't use an old starter with a new tube?
I'm specifically asking about home use where I can immediately stop using the light when it fails. In locations like shops and warehouses where a failed light may not be immediately noticed or fixed, a short-circuited starter would deteriorate the tube filaments and could even be a fire hazard, so preventive replacement may be warranted.