Writing a memo

Hi All,

I'm an auditor for a public accounting firm, and I have to frequently write memos for my inventory observation. Below is an example of a typical memo. My question is why are the words in BLUE are in present tense whereas the words in RED are in past tense? The red words is used as past tense because the observation took place in the past which I understand. However, I don't understand why the words in blue is in present tense. Is it because you're describing a thing/process?

Excerpt:

"ABC Corp. arrived at the main warehouse facility on January 5, 2010 to perform a count of physical inventory. ABC Corp. was greeted by the manager, who described count procedures and gave a tour of the warehouse. Per the manager, activity in the warehouse includes the receipt of whole engines bought from XYZ Company or sent by customers which are disassembled for refurbishment and then reassembled to sell. Some assembly occurs at the machine shop which is 3 miles from the main warehouse. ABC Corp. also visited this location and was assisted by the facility manager to complete the inventory observation."

Thanks!