It is much more complicated matter if you go into details.
Tech problems are always having the place. However to what extend the operator is prepared to deal with them? Many factors. One airline (especially very small) may opt for having just a small part of a no-go items in stock, while other may go much further and have extensive stock of spares. Which one is more likely to solve the tech problem?
One airline could have a contracted guy who is only good to top up the oil, other could have their own full-scale B1 & B2 guys at station. Again, which one is more likely to solve the tech problem quicker?
Some airlines having considerably more engine problems and even IFSDs than others, due to the different approach to preventive maintenance etc.
Airline with 3 aircraft cannot afford to have one spare aircraft. Airline with 50-100 fleet can. Blah-blah-blah.