Some journals, known as predatory journals charge large APCs without providing the peer review and editorial support that can be expected from a quality scholarly publication.
Common red flags associated with predatory publishers include:
And keep in mind, you can always contact your library subject specialist for assistance with assessing the reputability of a publisher.
Checklist (from Declan Butler, Butler, D., & others. (2013). The dark side of publishing. Nature, 495(7442), 433–435.)