STORING OF A MAGNETS.

• Magnets become weaker with time (due to ‘free’ poles) near the ends repelling each other and upsetting alignment of tiny magnets.
• To prevent this bar magnets are stored in pairs with unlike poles opposite and pieces of soft iron - keepers across the ends.
• The keepers become induced magnets and their poles neutralise the poles of the bar magnets.

https://www.le.ac.uk/se/centres/sci/selfstudy/mam8.htm