For those using El Cap, there is a bug in El Cap (still there as of dev preview 7), in which the built in Archiver has trouble unarchiving some zip files, either failing outright, or the hash values don't match of some items after unarchiving. I reported to Apple and provided a test zip file, created using Yosemite built-in archiver. Came across totally by accident, had a Yosemite created zip file, which unzips fine on Yosemite and Mavericks, and unzips fine under BetterZip, Entropy and Unarchiver, but El Cap failed in trying to unzip it. Was able to duplicate intermittently with other zip files created in other programs, ie. El Cap couldn't unzip them, or appeared to, but files were corrupted.
In the meantime, if using El Cap, don't rely on the built in Archiver to create or unzip. Use another compression product, which ever you like. this isn't a plug per se for BetterZip, nor am I against it, just a heads up to use a 3rd party product until Apple resolves.