It is given to few to peer inside the minds of the Hamas leadership, so their precise motives for rejecting the latest ceasefire offer cannot be easily discerned.
However, there are some consequences of their policy which are not difficult to determine. Many more innocent Palestinian people will starve to death, or be injured and die, more children will be orphaned, the remaining Israeli hostages will continue to be kept in tortuous conditions, the war will continue, and neither the state of Israel nor the Palestinian occupied territories will enjoy the kind of security taken for granted in most nations on earth. The slide into the abyss, in other words, will continue.