Most of us will have been in organisations that just couldn’t give up on an initiative that was clearly beyond saving. This occurs in our personal lives as well – we hold on to things (or ideas) and defend our holding on beyond what reason would really allow.
There is a very human reason for this; characterised in the ‘Sunk Cost Fallacy’: we have invested so much in something emotionally (but usually in most business contexts also financially or at least in terms of time ‘invested’) that we find it hard to give it up, in part because to do so seems to be to acknowledge some kind of failure .
A wholly rational being (one of Richard Thaler’s ‘Econs’ https://bit.ly/2SBAGzE) would happily pull the plug on a project that was going nowhere.
Humans, not so much.
Nevertheless, building an organisational discipline that allows you to call out projects or initiatives that are going nowhere is both possible and healthy. There are approaches that allow you to test decisions without blame and to draw a line without unhelpful recrimination.
Of course, sometimes when you hold on to something too long it may just get away on its own.
Not thinking about Mrs May’s Brexit deal at all.