Today, I get 12-months per piece and much of that is in peak condition. After 12-months I use the piece as a back up for when I want to wear something but not my most recent one (maybe that's why my prime piece is durable). Another key factor is the length of time I have worn - plenty of time to learn from mistakes and work out whats best for me.
At any one time, I have back up and spares as you never know. In fact, nowadays when I order I buy 2 pieces to build up my reserves. This was particularly important when Covid closed factories and stopped supply. Even today, there are after effects and delays so if you are committed to wearing always back up.