It's a sticky product. There isn't an alternative from Boeing in this market segment that's viable in a modern fleet from what I understand, and airlines tend t

It's a sticky product. There isn't an alternative from Boeing in this market segment that's viable in a modern fleet from what I understand, and airlines tend to be either Boeing or Airbus, so it would take a huge push to get an airline to migrate from one to the other – possibly multiple failed models and significant compensation to fund building up the maintenance infrastructure for the other manufacturer and pilot retraining.