I find it bemusing these days the number of people who say " no one saw it coming". Many of us saw it coming, now it transpires that Northern Rock, the bank the started the rot in the UK, was identified as the weak link in 2004 ... and that there was a serious risk of a domino effect:

Financial Times - Northern Rock risk revealed in 2004

Banking regulators identified Northern Rock as the weak link in Britain’s banking system during secret “war games” held as long ago as 2004, the Financial Times has learned.

The risk simulation planning, conducted by the Financial Services Authority, the Bank of England and the Treasury, made clear the systemic risks posed by Northern Rock’s business model, and its domino effect on HBOS, then the UK’s largest mortgage lender.

The revelation is at odds with the notion that no one could have foreseen the September 2007 collapse of Northern Rock or the subsequent rescue of HBOS, which was sold to Lloyds Bank.

Both banks sustained irreparable damage beginning in 2007 as wholesale lending markets seized up and mortgage-backed securities became unsaleable.

[see here also]
There's been a lot of tendency to blame the developers, the banks & FF for our woes, but these stakeholders should be in the firing line also:

1) Financial regulators & Central bankers : as per the above they knew about Northern Rock a long time back - In Ireland the Central Bank at least, seemed aware overheating was going on: why no action ?
2) Auditors : I have direct personal experience of one of the big 4 auditors frustrating some stress tests on the basis that they might produce "unexpected" results
3) Media : The Financial Times has been a beacon of light here, 5 years back it warned about MBS and the "opaque" nature of the market. Yet most other media were pretty poor, more interested in peddling property porn supplements than analysis
4) Retail investors/sellers : these people were tripping over each other to borrow more & more in an unseemly frenzy
5) The Opposition : Whilst FG & Labour aren't corrupt: would they have had better competence in governing this mess ? Do they sound like they've learned anything ?

So overall have/will the lessons be learned ?

Also is there a risk of people over correcting and avoiding risk too much ?

CyP