My view point will be based on QUALITY (ISO 9001) :
1/ ISO 9001 VERIFICATION :
Quality is compliance with requirements.
Testing is making sure requirements are fullfilled.
So a large part of the answer is :
What are the types of requirements that specifiers commonly forget.
If something is not explicited in the requirements, it can't be tested (tested against what : ? the tester opinion ?).
Example : usability.
Proper usability should be explored as part of functional analysis, with eg prototypes.
If it's not in this upstream phase, then it will raise issues in downstream phase for sure ...
Traceability is here not to forget testing requirements.
It implies some "requirement management" and in case there are "forgotten tests", it may be a good approach for improvement.
2/ ISO 9001 VALIDATION :
ISO 9001 also proposes to tests against intended usage (called "validation" as opposed to verification). This is when you drive the car live on the road to "test" it.
Here usability comes back in light ...
So here the question is : in the project construction, is there a phase like "customer validation" ?