For this job, all he needed was to show up earlier than the other several hundred men did.  He did need to be clothed.  That would help in the selection process.  Other than that, a strong, sturdy, and straight back was all that was required. Jobs are very hard to come by and hopeless men can be had for, well a dime a dozen!
To get to the job site required an early awakening at 5 a.m., and one hour walk to the loading dock.  This is where the strong, sturdy, and straight back comes in handy.  The dirt path is full of ruts, rocks and other hazards which can hamper carrying things on the back.  In order to do the 8 hours of heavy labor, this man would require the caloric intake of a cheeseburger.  This morning he had the equivalent of a cheeseburger, if you take away the meat, cheese, and mayonnaise. We can let him keep the pickle.

Each bag of beans, or cement, or maize or load of rocks he carries (depending on who is hiring that day) weighs the equivalent of 90 kilograms and must be carried a distance of 5-10 meters.  That is about 200 pounds carried for 15 to 30 feet.  I use metric measurements in order to make his load seem lighter and distance shorter.

For each bag carried, he will receive the equivalent of 1 Kenya Shilling, or about 0.75 US cents.  If he carries one dozen bags, he gets a total of 12 Kenyan shillings or about one US dime.  That makes it a dime a dozen.  If he works for about 7 hours straight and carries 100 bags he can take home 100 Kenyan shillings or about 80 US cents. That is if he doesn't break for tea (that will be 5 shillings) or to pee ( bathroom or bush break, depending on job locale).

Now of course mules could do a lot better job, you don't have to feed them cheeseburgers, and they do not require tea or privacy for relieving themselves.

Yes, labor in Kenya and much of the world follows this same pattern of man, mule or tools.  It is easy to see why at unemployment figures of 60-70% why it is easier to hire a men at a dime a dozen.