An anecdote:
Many years ago I travelled from France to London and I witnessed some of the groundworks for the future high-speed rails on both sides of the channel. On a weekend day, so no actual work was going on.

On the French side the groundworks were almost finished. It was just a wide smooth expanse of gravel that went on and on. The transition from where the gravel was compacted + graded to where it still needed work was a clear line. The site fencing was continuous and intact everywhere. The large machines were neatly parked together in separately fenced off areas, near that transition line between finished/to do.

In England the works looked not even close to finished. The gravel looked like they had been making a BMX track for jeeps, several very bumpy narrow paths next to each other, with ridges in between, without any section of the trajectory looking finished. It looked like they were working everywhere at the same time. Fencing was a jumbled mess. The many more + much smaller machines were haphazardly parked around the gravel (weekend). Parked on one of the hills of the BMX track there was the tiniest bulldozer that I have ever seen on a construction site that wasn't a renovation project, for such a massive project its prominent presence was hilarious imo.

With how the English worked on their part of the project, it was inevitable that they would be over budget, over time, and deliver with worse quality (with higher future costs for the client as a consequence).