Under One's Own Steam Meaning

(idiomatic) Using one's own resources; unaided; at one's own initiative.

Example: 1915, Victor Appleton, The Moving Picture Boys at Panama, ch. 12:
  Now the tug no longer moved under her own steam, nor had it been since coming alongside the wall of the central pier.
1980, Charlotte Vale Allen, Promises, ISBN 9781892738264, p. 265:
  I'd been wanting her to go for a long, long time, hoping she'd get up the gumption to do it under her own steam so I wouldn't have to make a scene about it.
1987 Aug. 18, "At the Fringe in Edinburgh, Theater in Crypt and Streets," New York Times (retrieved 27 July 2011):
  "People come at their own risk, at their own expense, under their own steam," said Mhairi McKenzie-Robinson, chief administrator of the Fringe.
2008 Sep. 9, Josh Quittner, "Steve Jobs: Not Dead Yet," Time:
  Jobs even briefly joined the media. . . . He walked under his own steam, of course, easily and without any apparent discomfort.