A companys accounts payable process currently has an average time of 6.4 weeks (5 workdays per week) between the time an incoming invoice is received and the time it is paid. Incoming invoices are processed by one of 16 AP analysts on a first-come, first served basis. The average amount of time an analyst spends processing an invoice to pay is 15 minutes, and each analyst has exactly 7 hours of worktime available per day to process invoices. Further, it is known that, on average, 200 new invoices arrive each day to be processed. Given these facts, what is the most likely explanation for the lengthy time (6.4 weeks) to actually get invoices processed and paid?

Group of answer choices

Excessively high analyst workload

High variability in the analyst processing time

Insufficient WIP storage

Low variability in the arrival pattern of invoices