“Prayer chains” are more like using prayer as a magic charm, as you mention an “expectation of good fortune” and often some warning about what will happen if you break the prayer chain. The Church discourages this type of “magical thinking” about prayer.
You should just pray sincerely and not be worrying about continuing a chain. There’s also no guarantee you will get “good fortune”, except that you will benefit from building your relationship with God.
I’ve been getting many messages recently on the order of “we’re praying for X, please join us in praying for X also, and ask everyone you know to do so as well.” without the superstitious good luck bits attached. It’s just a message of, “hey, let’s get as many people praying as possible.” I see this as distinctly different, and these ‘prayer chains’ (as they’re sometimes referred to) are perfectly fine.
It’s the things that have a string attached we disregard.
I recently received a “prayer chain” from a friend on Facebook Messenger which had two problematic elements.
It quoted Jesus saying “If you deny me before men, I will deny you before My Father in heaven.” The implication is if you break the chain, you’re denying Christ. That is a gross misapplication of this verse. There’s much more to “denying Christ” than declining to forward a post on social media. Including this in prayer chains can also be harmful to those with a scrupulous conscience.
It contained a promise “You will receive good news within 4 minutes.” This is rank superstition and a sin against the first commandment.
I told my friend off about the superstitious part. Also put him on ignore on Messenger.
DISCLAIMER: Catholic Answers has turned over the archive to Catholic-Questions.org and no longer owns, manages, or moderates the forums. For additional apologetics resources please visit www.catholic.com.