What incentive do you have to do a job quickly or correctly if you are being paid by the hour? Why would any company that bills by the hour want to improve their internal processes?

I have to work with accountants and lawyers who have hourly rates. They can’t tell me in advance how long any job is going to take because no two jobs are the same. I’m not a lawyer or an accountant so I don’t know how long it should take to complete certain tasks. When someone tells me that it took them 40 hours to produce a report what can I do other than believe them?

I have come to realise that this issue of trust means that I have to keep detailed records of the length of time spent in every meeting and phone call – because they are the tasks that I can monitor. When I receive a bill I check the cost of these against my records. If I find discrepancies I start to doubt the whole bill. For example, recently I received a bill for a three hour meeting. Now, I was at the meeting and it only lasted for 2 hours. So, if the company I’m working with can’t bill me correctly for a meeting that they know I was at how can I believe them when they are billing me for 40 hours of work that produced a report?