Friday afternoon a man works backwards through four jobsites in his head, lands on a number, and that number is what you pay him.

A man paid off two taps he made himself never has to argue about a number someone else wrote down — and you stop paying Friday's guess about last Tuesday. Everything downstream was left alone on purpose: approvals, payroll and job costs read the same hours figure they always did, only now it comes off two recorded instants.

The shop lands eleven grand over on labour and nobody can say whether framing or the roof steel is where it went.

Nobody on a roof wants to fill in which stage he's on — so he's never asked. The job is the only question put to him, and only when his crew genuinely has more than one running; the hours still land on the stage they were worked on.

A crew logs four days onto a build that was offered to them and quietly handed to somebody else, and the first anyone knows is a labour line on the wrong job.

A man who accepted the job on his own phone knows it's his, and nobody can say it went to the wrong number. An offered job showing up as somewhere to clock in would let hours pile onto work nobody agreed to take, and you'd find out from a cost report.

The schedule advances at lunchtime and eight hours of framing turn up on the roof steel line, where nobody ordered them.

A crew wants yesterday's hours to stay what they were — and so does the PM defending them in a meeting. Reading the stage at clock-out, or at report time, makes the hours change meaning every time the schedule moves; freezing it costs you the ability to re-cut history later, and that trade is worth making.

Six weeks on, an hour gets questioned and all anyone has is two people's memory of where the truck was parked that morning.

Honest crews shouldn't have to prove where they were every morning, and here they don't — every ordinary day passes untouched, and only an odd one, a clock-in half a county from the site, stands out on its own. A man who wanted to cheat it still can; what he can't do is cheat it invisibly.

One tap on a single bar of signal, nothing happens, he taps again — and a fortnight later payroll is sixteen hours heavy with nothing to say where they came from.

A man on a roof who taps twice shouldn't get an error to decode — he's handed back the shift he already has, so the screen tells him the truth and there's nothing to untangle on payday. One quick check answers am I on the clock, so the answer can be trusted.

A man leaves his phone charging in the truck at seven, and by the time anyone notices, his morning has to be reconstructed by two people who disagree about it.

Nobody should lose a morning's pay because his phone was charging in the truck, and the leader can fix it in two taps without anyone wondering later who typed what. The man goes on whatever job — and whatever kind of hour — the leader is on, because a crew works one site at a time and rides in one truck.

The missing Tuesday surfaces on payday, in front of the man it costs, with nothing left to check it against.

A leader wants to catch a mate's missed clock-in before it turns into an argument, not read about it on Friday. So it's deliberately a roster and not a report — the smallest thing that lets him fix this morning's mistake while it's still this morning's.

Somebody drives home still clocked in on Thursday and the nineteen-hour day turns up when payroll is already running.

A forgotten clock-out caught that night is a ten-minute fix; caught on payday it's a dispute. Twelve hours is counted from the clock-in that started the shift — switching between Job, Drive and Office / Shop doesn't restart it — so a four-in-the-morning start isn't flagged for being early. Who hears it is a setting: the owners and project managers, unless you point it at the leader on the same slab.

Every second Thursday somebody stands at your elbow asking what he is owed, and you put down what you were doing to go and count it for him.

A man who can see his own week doesn't have to stand at your elbow asking what he's owed. He's reading the office's own entries, split by kind, so payday starts from one sheet instead of two — and a missing day gets chased while the crew that worked it still remembers.

Two hours columns, and by March the payroll report and the P&L disagree by a hundred and forty hours with nobody able to say which is the real one.

The office shouldn't have to learn a second set of numbers, so the punched hours fill the same column approvals, payroll and job costs already read. A second hours field would have meant touching every report and giving two numbers a place to quietly disagree; the entry says which kind it's holding, and that was judged enough.

A disputed Thursday, and nobody can say whether that eight hours came off a clock, off a leader's phone, or off a sub's own paperwork.

A sub's company and your own men are paid differently, and both want their hours treated fairly — so each entry keeps where it came from: clocked by the man, entered by his leader, or submitted by a sub. That one distinction is what makes a labour dispute answerable without anyone reconstructing where eight hours came from.