For me it's about maximizing returns across various categories, maintaining diversity among lenders and networks, and having access to a variety of benefits that I want (all of them are never available on just one card).
In my case "5" was for the benefit of having a portfolio of different cards with different benefits. I'm done at 5.
I had 21 up until this past January.
My scores went up with each one, too.
I just app, get bonus, and then close before the AF hits.
That being said, I'll likely not app for as many cards going forward, as I have in the past. After my repo falls off this year, I'll be able to have an even better selection of prime cards to choose from (Ie ALL of Chase Banks offerings), and will no longer look for the easy cards, just for the sake of rebuilding, like I did 2 years ago.
In my case, I started out with low limits because of a lack of a credit history. It would be easy to hit 10% util on a $750 CL card in one grocery store trip. Having multiple cards allowed me to spread it, and not have to pay multiple times before the statement so my score does not take a hit. Responsible use of these cards allowed me to get better ones eventually with decent limits. I have a few store cards (4) and I got them for the discounts given to cardholders (30% discount at Kohls, etc). I'm hoping that with a "thicker file", creditors will see that I have managed it well and I can get a decent car loan and eventually a mortgage later on.
Interersting topic and timely for me. I don't want a slew of cards that I have to track and juggle, but it's important to have SOME.
Another reason for me: some cards have intro 0% APRs, which are handy if you are planning to make a big purchase, for which payments can be spread over a few months with no interest.
I know that for me it was because of a lack of understanding of how to use credit. I picked up the majority of my cards when I was in college, and just recently closed many of them that I haven't used in years. I'm reorganizing my credit portfolio and trying to only keep the ones I will actually use from here on out.
When I had a lot of baddies I tried to really open any card I could get.
Nowadays, I just try to take advantage of point and cash offerings. For instance, I had 4 Hilton HHonor cards and racked up a ton of points. I opened 2 Hawaiian Airline cards and one Virgin Atlantic card just so I could get the points and transfer them into Hilton points. The list goes on. Those with annual fees, if I don't use them anymore, I close before they hit. Some I just kept open because it can't hurt but I don't really use them - so there's no juggling.
In 2 weeks we are taking a trip to Costa Rica paid for by Hilton points "earned" from just cards. I believe it was $95 to book an all-inclusive resort. Then we used United points to book the 2 round-trip tickets (with the free bags!). I think we had to pay around $20 there. Then we decided to book a car rental that the DW used her Discover card rewards for. So basically for under $150 we're having a nice "paid" for vacation, food included with a rental car and round-trip flight from NY. This is just one example.
The sign-up bonuses are really decent on some cards if they're of use to you. One can really earn free trips/flights/cash just from sign-up bonuses ad maximizing points.
Other cards, such as the Freedom/BCP/Lowes, etc. give cashback or discounts when you use them. In my mind, why NOT have multiple cards?