1, Agencies determine the minimum standards. This establishes the lowest acceptable baseline for agency course quality.
2. Instructors determine the maximum standards. This influences the highest quality an individual course can be provided at.
How do agencies determine their minimum standards baseline?
A. Defining which assessed skills must contribute to a given course/syllabus.
B. Defining to what extent the instructor can interpret acceptable skill performance.
Most equivalent courses, across the spectrum of agencies, contain virtually identical skills. What differs is the tolerances applied to those skills, and what an instructor is directed to accept as a 'pass'.
As an example, let's consider buoyancy control. Here are different tolerances that can be applied to that fundamental skill:
1). Demonstrate effective buoyancy control.
2) Demonstrate effective buoyancy control for 15 minutes.
3) Demonstrate effective buoyancy control for 15 minutes, with no deviation from depth +/- 50cm.
4) Demonstrate effective buoyancy control for 15 minutes, with no deviation from depth +/- 50cm, in horizontal trim +/- 25 degrees.
As greater definition is applied to the performance standard, there is less freedom of interpretation for the instructor. Less freedom of interpretation reduces the opportunity for weak instructors to apply weak standards of assessment.
You can imagine how a sausage-factory instructor running 3 day open-water courses, for 8 students per course, might be tempted to interpret "effective buoyancy control' so that the course doesn't run over the stated dives/days. You can also imagine how an independent, tech-level, instructor running a private 1-2-1 open water class, with no set timescale, might interpret that same requirement.
A good instructor would gravitate to a higher
interpretation of #1... to the level of #3 or #4.
A bad instructor would
interpret #1 to the lowest possible order... in order to make performance criteria meet a timescale.
We, the consumer, could think of this 'freedom of interpretation' in the context of whether an agency
empowers good or bad quality training.
The mass-market agencies would think of this as empowering individual instructors to meet the demands of the market; where quick, cheap and easy training is the demand of most consumers. At the same time, they would not wish to limit or curtail those instructors/centers that wanted to target a smaller quality-driven student demographic and would voluntarily institute higher interpretations for that reason. This is, however, not the agency focus.
In contrast, niche or specialized agencies have an over-riding need to enforce good quality training. They are competing for the quality driven student demographic, where cost, timescale and commitment are lesser concerns. Reputation is important, so they cannot risk their instructors interpreting low definitions for skills.
Could a PADI instructor run courses with comparative difficulty/stringency to a GUE instructor? Yes.
Could a GUE instructor run courses to satisfy low-budget, low-commitment student divers? No.
Ultimately, it's the individual instructor who determines the upper boundaries of course quality.
The agency determines the lower boundaries.