Why would you cd somewhere and then do rm -rf * when you can just rm -rf somewhere?
Having your shell expand * is just asking for trouble; on most systems you'll have no problems creating more entries in a directory than you can specify arguments on the command line, so rm -rf * will not work from 'somewhere' but rm -rf somewhere should still work fine.
Having your shell expand * is just asking for trouble; on most systems you'll have no problems creating more entries in a directory than you can specify arguments on the command line, so rm -rf * will not work from 'somewhere' but rm -rf somewhere should still work fine.