Dismissal on a whim - why not?

[Citizen X]

This question was triggered by a post in the Metals Industry strike - my take thread.

I'll get to the post concerned in a moment, but first let me make an argument based on the same argument used by organised labour to support the right to strike (apparently balanced out by the employer's right to lock out, which come to think of it, the unions are not particularly respectful of right now ).

Argument 1.
The employee can resign on a whim. Doesn't even have to give reasons. Why can't the employer dismiss an employee in similar manner?

Argument 2.
I've highlighted the particularly relevant parts of the post.

OK then. How about when the employer and employee have a really bad relationship?
Like adversarial just for the sake of being adversarial because one doesn't like the other for whatever reason?

The employee can pick their moment to leave the relationship, but the employer can't?
Have you tried firing an employee for having a bad attitude?
Get ready to fork out at the CCMA if you do (or pay a hefty fee to a labour lawyer to deal with it).


Or how about when the employee is really miserable in their job, but can't muster up the initiative to move on?

I've had a few of these over the years, and they just suck the energy out of any room they enter and fill it with negativity.
I've counselled them.
I've tried motivating them.
I've offered options for them to improve their lot in life, which they just don't take.
They clock in.
They do the minimum asked of them.
They don't impress clients, or even lose you clients (as in they just go away and never return).
The only thing they cling onto stronger than their misery, is the cause of it - their job.

The absolute best thing I can do for them, my business, myself and the future of the rest of my staff is fire the misery's sorry ass and force them to move on.

But I'm not allowed to because that would be an unfair practice.

So come on - why not be able to fire the employee on a whim?
There's going to be a reason why that whim occurred in the first place, and as long as it's connected to the employee, I can't see a problem right now.
Enlightenment welcomed.

To lend perspective: The employee/employer relationship is governed both by common law and legislation. When an employee resigns on a whim, the only recourse an employer has is the common law route which is to sue for damages for breach of contract. This is a costly and time consuming route. Legislation regulates the circumstances under which an employee may be dismissed.
The concept of forum shopping is also connected to this. Many wonder why there is a labour court and yet many employees go to the high court. The reason is the very common law employment relationship.