In APUE, in figure 16-11, the code is as follows:

#include "apue.h"
#include <sys/socket.h>

#define MAXSLEEP 128

int connect_retry(int domain, int type, int protocol, const struct sockaddr *addr, socklen_t alen) {
   int numsec, fd;
   /* Try to connect with exponential backoff. */
   
   for (numsec = 1; numsec <= MAXSLEEP; numsec <<= 1) {
      if ((fd = socket(domain, type, protocol)) < 0)
         return(-1);
      if (connect(fd, addr, alen) == 0) {
      /* Connection accepted. */
         return(fd);
      }
      close(fd);

      /* Delay before trying again.*/       
      if (numsec <= MAXSLEEP/2)      -- question line
         sleep(numsec);
   }
   return(-1);

}

My question is: Why MAXSLEEP is define as 128 and It’s division by 2 is evaluated, and not defined 64 without any division?