1) Cannot read a file after you switch a software,
2) as if you can switch software
3) Someone send you a file that you cannot read,
4) Not without a proprietary software
5) assuming that the software is still available,
This would not happen if everyone stick with Open Standard and Open Documents.
- If the software not available for a variety of reason, people can build a reader/writer program to read your file
- A vendor will not take advantage of you, aka over pricing software etc
- A file(pictures,email etc) belongs to you, don't let people stop you from reading it.
So tell your friend, your co-worker, your boss, family, everyone about the importance of Open Standard, and Open Document.