Not really. If you are high up they do, but a lot of juniors end up leaving when times are bad because the union doesn't have work and so they are sitting in some union hall waiting for work making much less that minimum wage (unemployment) - if they find a job elsewhere to make ends meet when times get good they start at the bottom. Even if the job is with a different union they still start at the bottom, but more likely it is with a non-union shop hiring for a temporary job.
Each union is different. Not all of them have the above. However many unions are in areas where the business cycles affect them, some years there is more demand for their work than others and when there is a down year they can't provide stability for all members. When times are tight companies first stop building new buildings and so anyone in construction will have years of low demand.
Each union is different. Not all of them have the above. However many unions are in areas where the business cycles affect them, some years there is more demand for their work than others and when there is a down year they can't provide stability for all members. When times are tight companies first stop building new buildings and so anyone in construction will have years of low demand.