At the time, it was considered that keeping the occupational list up to date and having it absolutely current with the current labour market, given how quickly the labour market changes, was not a very effective way of making selection decisions for skilled immigrants, and that rather than identifying people based on occupational groups, what was more important was to focus on the total package that a skilled worker would bring to the country: their education level, their linguistic capabilities, their work experience in general, but not necessarily tied to a specific occupational group.
On May 13th, 2008. See this statement in context.