You are definitely headed in the right direction. Here are some things I would like you to think about for your revision.

I’m thinking that the type of order might have something to do with the wait time. We might find that some items or combination of items take longer than others. What might make one order take a significantly longer time than another? Just the size? Is there some way of comparing all these different combinations? If so, we could pinpoint the problem items and figure out ways to cut down their prep or processing times. Also, should the drive-up data be kept separate from the walk-in data or is it sufficient just to identify which is which in the same data base?

Collecting data during certain times of the day seems reasonable. Have you thought about the day of the week as a variable as well?

Have you considered that the complaints might mean something other than too-long wait times? What about customer relations? You know–friendliness, courtesy? Is there a way of getting at this possibility?

I think your timeline ought to include something about the time it is going to take to design the data collection forms and also maybe a training period for your observers. Shouldn’t there be some trial runs to catch any bugs and then some time to make any necessary modifications to the collection forms? Also, what about the time it will take to enter the data into spreadsheets? Considering the amount of data you will be collecting, entry time might be significant enough to figure in the timeline. Much of the data can be captured and stored by the computer as the orders are placed and so your observers need not write down everything at the moment.

I am pleased that you thought to include the services of a statistical consultant in this project because so many of my local managers did not. I suspect that either they didn’t even think of a consultant or were afraid that they didn’t know enough to deal with one. As a matter of fact, I think that you might consider bringing in the consultant at other times in the process, instead of just for the data analysis.

Anyway, give me a revision of your plan and timeline ASAP. I will let you know how we will deal with the cost and the accounting of the project later on.