[WalterSear]

From what I have read, you are most infectious in the 24-72 hour period before experiencing any symptoms.

Given that the time from infection to symptomality is as short as 48 hours, this means it may be possible to be infected by someone before either they or the person that infected them has started to show any symptoms.

[morsch]

There's a subtle distinction between being most infectious and infecting the most people.

You may be very infectious when symptomatic, but you're likely bedridden and the few people around you are taking some precautions.

On the other hand you may be less infectious while presymptomatic, but live a normal life, effectively infecting more people right before you "get sick" yourself.