How long is a workshop period?

When a show says it's in "workshops", how long is that usually? Is it always the same or does it vary depending on the show?
Also, do all shows have a workshop? I just am waiting for a show to get out of 'workshops' and want to know how much longer I have to wait! : P

Yeah, it's a case-by-case thing. Typically a couple of years for most musicals, I'd say. Some are less, some are more. Many don't see full productions.

And there isn't a real, set "workshopping" phase. Sometimes shows are mounted, then undergo more workshopping, then are remounted. They could be workshopped and then see no further work of any kind, other than quiet rewriting, for years- and then suddenly resurface in industry readings. Sometimes shows are commissioned by a theatre company and are bound by a schedule.

There's not a set path to the final product. Sometimes shows are written and move right to a major production with minimal workshops/showcases/readings. Sometimes they languish.

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