Client (a govt dept): we'd like a replacement roof exactly the same as the old one which is at the end of it's serviceable life.
Me: Wouldn't you prefer materials and designs that are newer, better and cheaper?
Client (a govt dept): no no, we know what we want, an exact replacement.
some time passes...... I return with spec and drawings
Me: ok here's the design for your roof, wadja think?
Client: there's no man safe system and it doesn't have a 25 year guarantee
Me: that's right, you insisted on an exact replacement, this is an exact replacement
Client: well it's got to be better than the old one, that's obvious surely?
Me: *^%$!£"! basssssstards