The formatting I made to my presentation were sometimes lost by PowerPoint after closing the file, and the next time I would open them my changes had been reverted to some odd default state. I’m not just talking about strange quirks that come and go without fanfare; the erroneous changes I’m referring to were frequent and demonstrable, and I was able to reproduce their effect for my co-workers easily.
In spite of the fact that this strange behavior followed an identifiable pattern, it remained inexplicable — I could find no clear reason why changing a typeface would not be retained the first three times I saved a file, but somehow the selection would stick the fourth time — and why this would happen on not just one, but two separate (but similar) files. A few of these wild errors were potentially disastrous, and had I not double-checked the files before sending them off to the client, they would have caused considerable embarrassment. This has been my experience with PowerPoint for the four or five years I’ve been working with it, and I’m tired of it.