Probation in contemporary workplace relations

I am often asked about the legal implications of an employee being “on probation”. Practically, in Western Australia, there are none. Although the Industrial Relations Act 1979 (WA) mentions probation as being a relevant issue in unfair dismissal cases where the employer is a sole trader or State Government agency in Western Australia, the workplace relations laws for the overwhelming number of WA employees is the national Fair Work system, where the relevance of probation has been wholly replaced with the minimum length of service required to be protected from unfair dismissal; ie 12 months in the case of a small business employer and 6 months for a non-small business employer.
Of course this does not mean that this has permeated down into real the real world yet where probation is still routinely a concept beloved by HR operatives; even though it is meaningless legally.