Why was the Edinburgh tram fiasco so expensive and late?

Fundamentally, rather than put the entire project in the hands of people who knew about, and were experienced in building tram systems, ( people on the continent essentially) the project was placed in the hands of inexperienced people,

The Edinburgh project was seriously mismanaged from the council staff and  councillors’ aspect. In the early stages the councillor responsible for
the project was changed several times, but was mainly “guided” by a director of  social services. There were no proper firm contracts drawn up, nor contract risks
defined, so the construction firms (who were also changed a number of times) could run circles around the naive council people.

No utility survey was conducted to find out what buried services there were and if they would have to be moved.  Services owners ( gas, electric, sewers necessarily require months of notice to mobilise and act so every time a new service was discovered this entailed a lengthy delay.

There were practically no records of cellars extending under the pavements from Georgian buildings in Princes Street, BT fibre optic cables ran diagonally
across the street, at a variable depth of sometimes about 3 inches, there was a main drain coming down the mound that was not recorded, no cost
overrun responsibilities were allocated, and with legal firm takeovers the lawyers created a goldmine of an internal market from their monopoly
position. The tram depot area was in a floodplain so serious extra drainage had to be organised, and the works on the roundabout there
(Gogar) was halted for about a year. At the council elections during this saga the ruling libdems virtually disappeared. Sue Bruce became the new
chief executive and assumed full control with a steel grip, and the tram project was transformed and completed, although much shorter than
designed. It is now a very successful operation, with almost overcrowded 42 metre long trams running during the rush hours (in normal non-lockdown

Local specialist groups such as cyclists were not consulted leading to an ongoing sage of injured cyclists dealing with badly designed cycle crossings.

So for tramway construction, do not take Edinburgh as an example to follow. Although the plans for reviewing the city’s transport organisation
promises new lines in a shorter time, with lessons learnt. I hope they are right, but this time the councillor responsible has experience of living
in Geneva, a tram city.