A small number of projects are finished ahead of schedule. Even projects who claimed to be on time often are against the latest commitment, not the originally approved target. This is relevant to almost all types of projects of all sizes and different countries. Why this is the case?

Because project optimisation does not happen automatically. Projects need methodology, tools and people who want to know optimisation methods and techniques.

The paradox is that planners/schedulers who work on project claims and can explain WHY PROJECT WAS LATE are paid much more than project consultants that could help projects AVOID DEALAYs.

As the result, when, for whatever reason, a portfolio (or even a country) has a project where time has a bigger priority than cost there are no specialists who know project management methods to accelerate delivery.