Notification emails haven't been sent out regularly in the past couple of years, for post removals. Even when they were, the reason given is almost always because one or more users reported your content. Well duh! That's the ONLY way content gets removed, so it's not helpful at all. To be specific would require human eyes to review EVERY SINGLE post that gets removed, to be able to select from a list of possible violations. That would require a number of employees due to the volume of post removals. Even Yahoo wasn't willing to spend that kind of money on the site, and Verizon seems inclined to spend even less (which is probably why we aren't notified of post removals anymore...so it's unlikely we'll appeal, because appeals need human eyes to review them).
You CAN post the exact text of your question or answer that was removed, in this subcategory (Yahoo Products>Yahoo Answers) and ask "Was this post a violation?" and the users here can tell you if it was (and why) or if it wasn't.
There are a LOT of posts on the site now that are chat (not knowledge seeking) and are violations, but many of them don't get reported enough to be taken down. Those are a common violation that a lot of users (esp new ones) don't realize are violations, since they are usually not insulting or offensive.
Think of it this way - the site was created to be a repository of knowledge and experience, for people to ask questions or for others to come here and peruse to find the information they were seeking. If your post isn't something that will get answers that may help other people too, then y our post is probably a violation.