A key thing I do to save a lot of money is buy my halyards 10 feet too long. Then every year or two I cut off 1 foot of the shackle end, and tie the shackle on again. This moves all the wear points on the halyard by 1 foot. It's at the wear points that the halyard will fail, so by moving them I extend the life of the line by years and years.
I know its cocktail hour, but the OP wants to know about RUNNING rigging, NOT standing rigging. When the running rigging gets too old, it will let you know. Replacemenbt is a DIY job for most folks.
Ooooops. Sorry.
When it breaks. Except for halyards which is better to replace before they break.
One tip... rich racing yachts sometimes throw out near new rope at the beginning of a season. So its a year old.
So make friends with idiots