Seniority: for better or for worse.
Seniority for all it's ills is the only way to ensure a fair system of opportunity to qualify for Command. The desirability of the position of Captain {given the years hard work, testing and training and then years of flying crap aeroplanes for crap pay and working for crap management} is mainly due to finally achieving some of the professional respect and recognition both, remunerative and social, that most professionals achieve in at most about 5 -8 years.
Given that everybody wants to be a Captain and that we all (professional pilots flying the line) pass the same tests to {hopefully} the same standards, the only way to prevent the 'conga line of suckholes' that is some companies way of managing a business is to ensure that there is an unbiased criteria for selection for the coveted 'Opportunity to Qualify for Command'
Please remember: It is nothing more than that - 'Opportunity to Qualify for Command'. You still need to make the grade and I am personally glad it is HIGH. Even so, there are pretty variable standards at times, with some getting through or promoted to training/checking positions because of 'connections' rather than suitability. Seniority is not infallible but it is the best solution to a difficult problem.
To those that draw parallels with the corporate world please remember how many 'Executives' die at their desks with all their customers dragged along for the ride. Call me arrogant or what you will but I am an aircraft Commander and daily take on a level of responsibility that would make most 'wannabes' eyes water. I am immensely proud of it and relish the daily challenges professional aviation brings.
How many CEOs make decisions with potential liability in the hundreds of millions, sometimes in just a few seconds and without a team of nodding yes men and dozens of meetings? You want to know about time pressured decision making? Then look in the cockpit of a modern jet airliner on min gas at a piss ant airport with third world ATC and weather at the minima!
I am afraid that a forum filled with, albeit interested and generally well meaning folk, who are NOT qualified as professional pilots is at best a discussion and should not be taken as meaningful in the determination of how we decide who gets to sit in the coveted LHS.