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Short answer
Hamas has been holding over 130 Israeli hostages since October 7th. Despite multiple negotiations, they refuse to release them. Israel plans to involve Rafah to confront remaining Hamas forces. Additionally, Israel provides safety measures in Rafah to minimize civilian casualties in the conflict. It seems Hamas has no concern whatsoever if Israeli forces enter Rafah or if they defend their population
Long answer
As of the time of this writing, Hamas holds over 130 Israeli hostages still at their mercy since October 7th. Despite numerous efforts reported in the media of multiple negotiations by Qatar, Egypt, & the US, Hamas has not budged on its claim to hold these hostages. Furthermore, Hamas releases propaganda videos showing the hostages speaking as a way of intimidating the Israeli & western public. Since the negotiation does not yield results and Hamas continually denies hostage release, Israel has stated that it must involve the Rafah region and begin its plan to eradicate the last few standing Hamas battalions that Israel has yet to fight with. Hamas, as at any stage of the war, could have ended any harm to any non-combatant civilians by surrendering and releasing the hostages voluntarily.
In addition, it has already been shown that Israel provides safety corridors and warnings for the civilian population in Rafah, so it will diminish civilian casualties while carrying out this war against Hamas, which again bears the sole responsibility for this war
