Three reasons.
Then buy.

1. Reuse

Stop tossing spools. Remount filament. Repeat. Official how-to: refill onto a reusable spool.

2. Cost

$9.99 once. Bulk filament forever after. Compare to official reusable spool.

3. Fit intent

Sized for common Bambu AMS-style use. Details: compat · AMS spool size specs.

Want essays?

Go deep on reuse benefits or AMS benefits. FFF basics: FFF printing basics.