Loyalty programs are often joined casually at checkout for a one-time perk, but their real value usually comes from how they compound with regular use, not from the small welcome discount most programs offer on sign-up.
Most loyalty programs convert spending into points at a fixed rate, then let those points be redeemed for a discount, a free item, or store credit once a threshold is reached. Tiered programs add a second layer on top of this, unlocking better earning rates, early access to sales, or exclusive discounts once a shopper's spending crosses set thresholds within a given period. Because tier status is usually evaluated annually, spending that is spread out unevenly across the year can cause a shopper to lose a tier they had reached the previous year even without a real change in overall spending habits.
Not every loyalty program is worth the effort of tracking, and a few questions help separate the useful ones from the ones that add little beyond an email subscription.
The last point is worth taking seriously, since a discount earned through a loyalty program only represents real savings if the underlying purchase would have happened regardless of the program.
Loyalty discounts are usually allowed alongside sale prices and, in many cases, alongside a separate discount code, since the loyalty benefit is typically applied as store credit or a point redemption rather than a percentage taken directly off the item at checkout. Checking a program's terms for exclusions is still worth doing, since some retailers exclude clearance or already-discounted items from additional loyalty point earning even when they allow the points to still be redeemed.
Loyalty programs reward consistency rather than any single transaction, so their value is best judged over months of regular shopping rather than by the size of the discount offered at sign-up.