Hi dude,
The main reason is, this is the very beginning and often if newbies feel 'overfaced' with a big pile of exercises to do, it's a putoff.

There's no harm in doing them more than once a day if they are found enjoyable, but like anything else excess is not beneficial, so moderation in all things is a good guide. It's good to try everything once, because later we'll be selecting our favorites.

Some hacks / exercises can only be done once a day (for example some NMS work)and some are best repeated a number of times, this is covered in later tutorials (but by then we have narrowed down the exercises to the specific ones we personally need.)
Best,
AR