The first chapter of "David Copperfield" is "I Am Born."
Following a chronology worked for Dickens but it is usually a disaster for speakers. Look at the expressions of the audience members. Watch as the eyes dart about the room. I can tell you what's going through their minds:
"How do I get out of here?"
"Now I know why that back row filled so quickly."
"Ten more PowerPoint slides and I will slip into a catatonic state."
"Ellen's looking good. I wonder what she's doing for lunch."
"Tahiti. No, Hawaii. No, Tahiti."
"Baxter had a heart attack yesterday. Lucky bastard."
That's why you want to plunge your audience into the story.
Remember the technique of thriller writers: Give the third chapter first.