Not in any ranked order, but one person's opinion, these are among the plusses....
- ++ ease of writing (ie, testing, revising, testing!)
- ease of revision
- perl DWIMs
...and these, perhaps minuses...
- compilation at run time can (but, does NOT NECESSARILY) impose an unacceptable cost
- distribution: all users must have access to perl binary (or you must use one of the "compilers")
- sometimes what you thought you wanted (and what you coded) wasn't what you really meant
You'll also find other threads here on this with more precise or technical info.