This time it happened TO me.
I was flying out of Bangalore the other day and we had to return to the ramp because of a maintenance issue. We were loaded within a few thousand pounds of the max we could take off with from the runway using every trick in the book.
Unless you are someplace that has an extreme "something", short runway, high altitude, high temperature, both, among others; it's likely that the plane you are in is taking off at 75-90% power to take it easier on the engine/s. The most likely time for an engine to fail is at max power, on takeoff, at the first power reduction. In the last 20 years on jets, I've made a handful of MAX BLAST takeoffs. Nearly everything is "reduced thrust" to some degree or another. As a bonus, less noise as well. The main reason SNA is a pain to operate in and out of on a good day. NIMBY.
Bangalore is high (3000') and hot, in the 90's for us that day.
So the problem gets fixed, but in the intervening 3 hours, the temperature goes up 6 degrees, enough to put us 500 lbs overweight on a 950,000 airplane. We run out of duty time for the flight and go to the hotel for rest. Come out the next day and are set to use the other runway that has 6000#'s less capacity than the one from the day before. Nearly can't get out, because we were getting stuck behind so many "hometeam" airlines that we almost had to go back for more gas for the 11 hour flight to Germany. If we'd had to, I suspect we'd have been bumping freight to make weight again.
As it was we had to use Max Thrust, max Takeoff Flaps, AND turn off the pressurization for the takeoff to get all the goodies they wanted on the jet to Germany.
So for the OP's scenario, SNA has a runway 40% shorter than "we'd" like (I can never have enough gas, unless on fire, or runway ahead of me), higher than average initial climb performance required for noise, and it was probably a warmer day there along with a longer flight to make. A higher temperature thins the air making it "feel" like higher altitude to the airplane.
You will find similar situations in PHX (raw heat & a little altitude) and DEN (heat and lot more altitude) in the Summer. Some of this is offset by adding pavement, DEN built a 16000' runway, roughly 50% longer than average so that the planes bound for the Far East, nonstop could carry the maximum load that distance, in the summer.
In your case, it was probably unexpectedly warm weather in SNA that the airline hadn't adjusted loads for, for the season yet. When Summer shows up out there, the airline likely plans to sell less tickets so your scenario happens less.
That is about as shallow in the rabbit hole I can go and give you an explanation as to why the airline wasn't pulling a fast one.
