(Yawn) I thought union debates were settled decades ago.
In whose favour?
Sadly, such a system would rapidly become unmanageable for employers, who would need to track different pay rates and increments for each employee.
That is already the case.
Well, no, it often isn't. Typically there are a handful of pay bands for a given role, and everyone is paid one of those bands as a base wage.
Most employees get different rates: new hires, 5-year vets, 10-year vets, different shifts, etc.
Raises are paid by years of experience, skill levels, etc.
Even among union members.
Do all bus drivers get the same rate?
We get paid one of seven band rates as a base wage, plus allowances and extra payments that are calculated via a standard set of formulae (eg 150% of basic for time worked in excess of 38 hours in a given week).
My employer would certainly baulk at being asked to maintain a separate basic wage for each driver - that would be a hundredfold increase in the complexity of the payroll.
Obviously it would be fairly easy to implement such a system today, if that was designed in from the start. But our payroll system was computerised in the 1970s, and big chunks of it are still written in COBOL. It would be a massive and expensive project to attempt to replace it.
And I say "attempt", because
recent history with such projects suggests that failure is a very likely outcome.
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My union experience (I know, nobody asked):
As a teen I had to join the IBEW (International Brotherhood of Electrical Workers)
to get a job assembling lamps after school. My shift was all students.
I couldn't even go to the union meetings, because they were held at night, while I was at work.
My shift manager was my union rep. (The same guy I would complain about given the chance)
That sucks.
I presume that you are aware that it's not typical, at least, not worldwide.
The US seems to be as uniquely bad at unionisation as she is at healthcare.
I suspect the hideous corruption of the US system has its roots in the massive boost to organised crime that resulted from Prohibition, which was contemporary with the rapid growth of trades unionism between the wars.
Labour unions were just another power base corrupted by gangsters, at a time when gangsters were given a blank cheque by the Eighteenth Amendment.