Properly used condoms can fail, but it's very rare. I've experienced it myself. It was a cheap very generic looking Lifestyle brand condom, never saw one like it in a store. I've never, not once, had a failure with normal shit I've bought at the store. Of course each brand has a wide array of models, so some may be shittier than others. I'm not implying all Lifestyle condoms suck, just that particular type was something I've never seen before. Maybe something she got on amazon, possibly meant for a non-US market. Either way it was clearly a piece of shit and thankfully nothing bad came of this.

That being said, the vast majority of condom failures which lower the advertised failure rates by manufacturers themselves, are human error related. For example:

• More than one condom at a time causes failure, people still spread the double bag shit around schools.
• Lack of adequate lubrication. Use lube especially if she's not wet enough, shit's cheap. Feels good for everyone.
• Wrong lube used. Not all lubricants are safe for condoms, toys, etc... they eat away at the material.
• Improper application which can cause damage to the condom. I've seen chicks dig into a condom with their nails to stretch them like a rubber band and snap them on instead of rolling them on. I don't care if you're thicker than a coke can that shit's going to roll on with a bit of effort.
• Not leaving space at the reservoir tip.

Once you weed all those errors out, the actual failures are really low. People always ask how much risk there is when using the pill, condoms, etc.. The answer is if you're not fucking it up and not buying suspicious condoms/pills from fuck knows where, it's more likely you'll get hit by a truck crossing the street tomorrow. Especially with the pill, really you'd have a better chance of winning the lottery jackpot if you're not fucking up and missing doses.