Doing due-dilligence doesn't mean you always get it right, but...

Doing due-dilligence doesn't mean you always get it right, but it does mean being aware of and accepting the risks going in.

I definitely think the price got to high and priced in too much blue sky, I think the market was probably predicting quicker earnings and less capital being required.

Its apparent that "fitting-out" is quite capital intensive, and the decision to bring more of that fitout forward makes it even more demanding.

You also can't just look at NextDC in isolation either. In Sydney GlobalSwitch is currently constructing its new DataCentre adjacent its current one. Its going to be even bigger than the current one which is already massive.
Being an established player, it already has a lot of relationships with current businesses. NextDC still has to foster these relationships.
GlobalSwitch is but one example.

If you form the view that these large high quality Data Centres will pull racks out of onsite server rooms/older lesser quality Data Centres, you have to realise the rate of this change will be largely contingent on prevailing economic conditions/business confidence.

The fact of the matter is that until a company can be valued on earnings its price is purely speculative and subject to massive price swings.