AscotexgunnerNewCorkSethStranded "Big" in most cases just means were successful at some undefined point in the past.
In 20 or 30 years time, quite possible that we could be seen as a big club, if we are long term settled in the top flight and won a couple of things whilst Forest could still be bouncing around the Champ/L1 and not be seen as one i.e. a Preston.
How long is a long time? Stoke, Southampton and Bournemouth all had or are having fair periods of top flight football but don't think anyone would consider them big clubs.
West Ham also comes to mind.
Will Wolves ever be a big club for example? Reckon they are one manager change away from dropping like a stone.
On the phone in last night couple of Wolves fans wanting a new manager. They were calling for Benitez (which always makes me laugh). It's like Alan Curbishly and Charlton never happened. It's amazing how being a bit successful goes to fans heads.
To be fair, Curbishley left Charlton almost 15 years ago. I suspect quite a lot of those Wolves fans were children back then.