The company I work for unionized a few years ago.
Just to give everyone an idea of the difference between unionized and non-unionized work:
county: Israel
Sick days:
Before union: paid as required by law (first day not paid, 2nd-3rd 50% daily pay, 4th and on 75%)
After union: paid 100% daily from day one.
Salary:
Before union: fixed, you could negotiate your salary but nothing promised a raise at any point.
After union: fixed starting salary, negotiable after 1 year, yearly raises for workers over 4 years based on performance regardless of any other raises given during the year (2%-5% raise)
Convalescence fees:
A short explanation because idk how this works elsewhere in the world.
Here every worker over 1 year is entitled to a yearly bonus that is calculated as follows:
1-2 year hourly pay*8 (8 hour work day)*job partiality percentage*Factor
Factor is determined by law as follows:
1-2 years Factor=5
2-3 years Factor=6
4-10 years Factor=7
11-15 years Factor=8
15-20 years Factor=9
20+ years Factor=10
Before union:
a worker that works part-time (say 75%) for 30 ILS would get 30*8*0.75*5= 900 ILS
a worker that works full time for 40 ILS would get 40*8*1*6= 1920 ILS
After union:
the factor stays the same, so does the percentage, but what changed is how the pay is calculated.
as long as Hourly Pay*8 >500 you get 500 ILS
meaning the same workers as before, the first one would get 500*0.75*5= 1875 ILS while the second one would get 500*1*6= 3000 ILS
firing any worker over one year requires a legitimate reason from a list of posible ones from the union's aproved reasons, firing a worker of over 4 years requires authorization from a union representative and can be made either after said worker did something extremely harmfull or after a process that lasts over 6 months,
in which the worker can demonstrate improvement and so wont need to be fired.
there were many other changes that benefitted both workers and company, but those are ones i remember and have seen in efect.
the workplace has turned so much better after unionizing and most people are actually glad to be working there, it made a huge impact for all of us.