Maybe we were just spoilt by the quality of First Class and Days of Future Past, but X-Men: Apocalypse never lived up to its brilliant trailers. Sure, the later trailers were definitely full of too many spoilers (we didn't have to know that Wolverine would show up, dammit!), but watch them back now and you can't say that they aren't full of more emotion, style, and substance than the finished product.
Okay, the film wasn't entirely bad, it just wasn't as good as we've come to expect from our favourite mutants in spandex. Apocalypse wasn't as interesting or exciting as he first appeared, and there are only so many times we can watch Xavier reach out to Magneto and try to convince him there's a better way to rule the world. Plus the third act felt overly familiar.
There was also the suggestion that Psylocke, a hugely anticipated character in the cinematic X-Men franchise, was going to be a much more formidable foe. Here's hoping the next time a new character is hyped up in a future X-Men film they actually, I don't know, have some effect on proceedings.