You're right, the Tiger platform only undergoes significant changes every other
year or so (tramp, daggers, mast, boom).

But reality is, if you want to stay competitive you need a new set of sails
every year (Main, jib, spi. Both due to wear and new cuts).
The price difference between buying a new set of sails (+/-€3K) or trading-in
for a new boat becomes so small that most people buy a new boat instead.