If you have users using different languages, you have to make sure that when they modify text on a box that shows the little blue flag on the upper-right hand corner, they click on it and enter the translation into all other languages, or at least, remove the old text (translations) from the list.

Let me explain with an example: I uploaded several products (ex. "Instant Demo"), and I have my Odoo language set to English. Then my co-worker, who has the Odoo language set to Spanish, updated those product names (ex. "Instantaneous Demo"). As a result of this update, Odoo created a Spanish "translation" for all those product names, and kept the English "translation" with the original, uploaded, text. All users using English as their Odoo language were seeing the old/original text ("Instant Demo"), while all users using Spanish were seeing the new/updated text ("Instantaneous Demo").

I hope this helps someone else.

If you encounter this problem, you might be able to fix it by going to "Translated Terms" under "Settings --> Translations", and searching "Translated field" for "product.template" (in my case) and "Type is Object". Then fix all those missing translations (hint: export, fix, import).