Why reissue identity cards to employees in every few years?

Why the management have to reissue identity cards to their employees in every few years?

Change in appearance-like youngster with no grey hair and now after many years.
Contents of Identity card may become illegible also.
Change of department/place of work etc.
Loss of original card.
There are many such reasons for reissue of I-card

Beyond agreeing with Mr.Nath Rao, certain other points also like change in emergency contact details, change in designation (after upgradation) for few employees,change in authorised signatory of the company who signs the cards etc also can cause a re-issue.

Incase they had a promotion,change designation.

To deal with changes happened to an employee that may be: Change of department, designation, mutilated or any newthing management wants to put or many times magnetic interface does not work.