Stamps

[ldy josie x]

I wasn't sure which Help forum to post this in, but I'm pretty sure it fits in this forum too.
Anyways---
When some people receive their envelopes in the mail, the stamps on the envelope are NOT canceled out (meaning, they can reuse the stamps). Other people, however, receive their envelopes with the stamps are crossed out and canceled (so it is impossible to reuse them).
Why is that (the whole uncanceled vs. canceled)?

[nowandagain]

Hi Josie

Postmarking stamps/envelopes are to cancel out the postage to indicate that the postage has been used.

In some instances, envelopes are missed by the cancelling machine for a number of reasons - human error, bulkiness, time ...

Normally, envelopes that cannot go through the cancelling machine are cancelled out by hand (using a stamp or crossed out). Even in this case we still see some envelopes arrive without any markings for numerous reasons.

Really, all envelopes that go through the post should be cancelled out. In practice, this isn't always to be the case ...

nowandagain [rockon]