Why your schedule always runs over, and how to fix it for good

Below are the three causes that bring overruns back time after time, and what to do about them: from a buffer that actually holds to the point where fixing things by hand reaches its limit.

Why does your schedule keep running over?

Overruns are usually not an incident, but the result of three recurring patterns: jobs estimated too tightly, travel time that isn't in the schedule, and a buffer that exists in theory but is the first thing to go in practice.

Each of the three is enough on its own to make a day slip. Together they make overruns not the exception, but the norm.

Cause 1: you estimate the length of a job too optimistically

Most business owners plan on how long a job normally takes, not on how long it takes this time. A boiler service that usually takes 45 minutes can easily become an hour on an older installation. If you routinely plan that time too tightly, the overrun is not the exception but the average.

This is called the planning fallacy: people consistently estimate their own tasks too optimistically, even when they know it took longer last time too. So don't look at how long a job takes in theory, but at how long your last five comparable jobs actually took.

Cause 2: travel time isn't in the schedule, but between it

A second cause isn't in the appointment itself, but in what sits between appointments. If you don't count the drive to the next customer as part of the appointment, that time doesn't disappear. It simply gets nibbled off your next block.

An engineer who expects to be done at 2 pm and only then starts the twenty-minute drive to the next customer is, in practice, not on the road until 2.20 pm. On paper the schedule was right. In practice they were already behind at the first appointment.

Cause 3: the buffer you schedule is the first thing to go

Most business owners know by now that they need a buffer. The problem is when you schedule it. Put the buffer in at the start of your planning session and by the end it has almost always filled up with something else: an extra customer, a longer job, a request you squeezed in after all.

A buffer only works if it is the last thing you lock in, not the first. Once it is the final step in your schedule, there is nothing left that can push it out.

How do you schedule a buffer that actually holds?

Scheduling a buffer that works comes down to three choices: where you put it, how big it is, and who gets to touch it.

Put the buffer at the end of your day, not between appointments. A buffer between two appointments gets filled almost automatically as soon as a customer calls who “could just squeeze in”. At the end of your day that temptation is smaller, and an overrun earlier on has somewhere to slide to without your last customer paying the price.

Plan for fifteen to twenty percent of your total working time. Less than that rarely solves the problem. More than that makes your calendar look emptier than it is, which in turn makes it more tempting to put an appointment in it after all.

Treat the buffer as an appointment with yourself. Literally put it in your calendar, not as empty space but as blocked time. Empty space in a calendar gets filled sooner or later. Blocked time doesn't.

Want to build this into a fixed weekly routine rather than a loose principle? Then read how to build a weekly schedule with the 30-minute system, in which the buffer gets its own fixed block.

What do you do when an appointment runs over anyway?

Even with a good buffer, something will run over now and then. The difference between a day that gets back on track and a day that falls apart lies in what you do at that moment.

Move the next appointment, not your whole day. Call that customer as soon as you know you are running over, not when you are already late. And use your buffer as the first safety net, before you start moving other appointments. The same logic applies just as well within a single day: in the post on a daily schedule that holds up when you work on location I work out how to apply it day by day.

Why doesn't a good buffer solve everything?

A buffer absorbs what goes wrong within a day you planned yourself. It doesn't solve what comes up before that day begins: the call from a new customer, the question whether an appointment can move an hour later after all, the request that has to fit between two existing jobs.

Each of those moments asks for a decision from you, and each decision costs time that wasn't in your schedule. However tight your buffer is, as long as you are the one assessing every request, something can still disrupt your day before the first appointment has even started.

How do you stop new requests from filling your buffer after all?

You stop it by not just reserving your buffer in your head, but by actually making it unavailable for new bookings. As long as customers still come to you to ask for a time, the temptation to say yes remains.

With Schedulinq you set your availability in advance, including the buffer you want to keep. Customers book a time themselves through your personal linq, but simply don't see the time you have blocked off as an option. Then there is nobody left who can talk you into filling that space after all, because the choice is no longer yours to make in the moment.

On top of that, Schedulinq only offers time slots that keep your route efficient: it looks in advance at the route you are already driving that day. A new appointment is never squeezed in between two customers on opposite sides of your service area, which removes one of the most common causes of overruns before it happens. Tested across 54 different scenarios, that gives an average of 18 percent less travel time and room for 20 percent more appointments per day.

That is the difference between a buffer that sits on paper and a buffer that actually protects your schedule.

Try Schedulinq free for 30 days: no credit card needed, no automatic renewal. After that it costs €29 per employee per month, excluding VAT, with unlimited appointments.

Tackle overruns at the cause, not the symptom

A schedule that keeps running over rarely comes down to one busy day. It comes down to three recurring causes: jobs estimated too optimistically, travel time that wasn't counted, and a buffer that is the first to go because it was scheduled at the wrong moment. Place your buffer at the end of your planning session, count travel time as part of the appointment, and estimate jobs on what they actually took before, not on how long they take in theory.

What remains are the requests that come in along the way and that nobody can plan in advance. A better estimate won't help there. A system that already guards your buffer and your route before a new appointment exists will.

Try Schedulinq free for 30 days and build a schedule that doesn't fall apart again every week.