Semi-automated offside technology does what it says. Multiple cameras track limb positions many times a second, the system identifies the moment the ball is played, and it generates a decision in a fraction of the time the old manual line-drawing took. As engineering it's genuinely impressive.
And the complaints haven't stopped. They've barely even changed. Which suggests the problem was never really about how long the check took, and that's worth thinking about properly.
What the technology actually fixed
Two things, both real.
Speed. The old process involved an operator picking a frame, drawing lines by hand, and calibrating them to the pitch. It took two or three minutes on a bad day and the crowd stood around waiting. Automated systems cut that down substantially, though not to zero — there's still a human confirmation step in most implementations.
Consistency. Manual line-drawing had an irreducible element of judgement. Which frame is the moment of contact? Where exactly does the defender's shoulder end? Different operators made slightly different calls. Automating it removes that variance, which is a genuine improvement in fairness even if nobody feels it.
What it didn't fix
The actual grievance, which is that a goal can be disallowed for an offence nobody can see and nobody thinks matters.
When a striker's armpit is three centimetres beyond a defender's knee, the law has been broken. That's not in dispute. What's in dispute is whether that's an offence in any meaningful sense — whether it represents the kind of unfair advantage the offside law exists to prevent.
Speeding up the detection of a three-centimetre offence doesn't address that at all. If anything it makes it worse, because the decision now arrives with an air of computational authority. The system says offside, therefore it is offside, and the argument about whether it should be is closed before it starts.
The measurement precision illusion
Here's a technical point that gets underdiscussed. These systems produce a decision, and the decision is presented as binary, but the underlying measurement has an error range.
Limb tracking from optical systems has uncertainty. Ball-contact timing has uncertainty — the ball deforms, contact happens over several milliseconds, and the frame rate imposes a granularity. Camera calibration has uncertainty. All of these compound.
Published tolerances vary by system and by installation, but nobody credible claims sub-centimetre certainty on a moving limb. Which means that when a decision comes back as offside by two centimetres, the honest statement is "offside, probably, within the resolution of the system."
That's not what gets displayed. What gets displayed is a clean animation with a decisive line, and the animation is a visualisation rather than a measurement. It's designed for broadcast clarity, and clarity here means overstating certainty.
The fix that isn't technological
If the problem is that trivially small offsides are being penalised, the solution is a change to the law, not a change to the equipment.
Several proposals exist. A tolerance band — offside only if the attacker is clear by some margin, say 10 or 20 centimetres, which would resolve most of the controversial cases. Or the "daylight" rule, where any overlap between attacker and defender means onside. Or restricting the offside judgement to specific body parts rather than any part that can score.
All of these have been discussed at length in the game's rule-making bodies. All of them have obvious objections — mainly that they move the line rather than removing it, so you'd get the same arguments about a different threshold.
That objection is true and I don't think it's fatal. A rule where the marginal cases are 20 centimetres rather than 2 centimetres produces far fewer marginal cases, because bodies are more often either clearly beyond or clearly not. The distribution isn't uniform.
The thing technology genuinely changed
One consequence that I think is more significant than the offside decisions themselves: defenders stopped stepping up.
The offside trap as a deliberate tactic relied on marginal calls falling the defence's way more often than not, which they did when a human assistant with an imperfect view was making them. Precise measurement removed that, and with it removed the strategic value of the aggressive step.
That's a real tactical change caused by a technology change, and it's had more effect on how football is played than any of the individual decisions everybody argues about.
Where it goes next
The direction of travel is towards more automation, not less. Chip-in-ball technology for contact timing, more cameras, higher frame rates, and eventually fully automated calls with no human in the loop for the clearest cases.
All of that will make the system faster and more precise, and none of it will make anybody happier, because the dissatisfaction was never about precision.
The engineering question was "can we determine offside accurately." That's been answered, more or less. The question that actually needed answering was "what should count as offside," and that's a sporting judgement that no amount of camera resolution will resolve. It's slightly odd that the sport spent a decade and a great deal of money on the first one.