Say you noticed that software you released had a bug. Only minor
changes were necessary to remove the problem, but once you did them, you needed to re-send
your customers the complete version. This might be expensive for you, if you have to do it
by postal mail. And it would possibly be a problem to the customer it you sent it by
email. Anyway, sending the patch file instead of the full version would do one of these:
- No re-installation, save your customers from this experience
and possible problems like re-entering serial numbers involved.
- Make fast transmission via email possible. Updates of large software
package normally could not be sent via email and therefore you'd not have the benefits of
it. Email will take minutes instead of days and no postal fees.
- Or make transmission via email more tolerable with small patch
file attachments install of the full installation version:
Figure A: Minor bug fix to a Windows Software
Full Installation Version | 1570 kB |
Executable Patch File | 35 kB |
Plain Patch File | 1,7 kb | 
- And last but not least: You demonstrate competence by
providing a fix in a convenient way to the end user.