Chizkiyahu HaMelech (King Hezekiah) did not become Moshiach primarily because he failed to offer proper praise or gratitude to God after the miraculous defeat of the Assyrian army, despite being considered a prime candidate for the role. According to the Talmud (Sanhedrin 94a), God desired to appoint him as Moshiach, but this opportunity was lost due to his lack of hakarat hatov (gratitude).24

Traditional sources provide specific details on this lapse:

• He declined to recite Hallel (Psalms of praise) following the supernatural destruction of 180,000 Assyrian soldiers besieging Jerusalem, as recorded in II Kings 19 and Isaiah 37, because the victory felt incomplete—much of northern Israel had already been devastated by the Assyrians.36
• This stemmed from grand expectations for a perfect triumph, blinding him to the miracle's significance, which postponed his Messianic potential.3

The Sages (Chazal) explicitly state: "The Holy One, blessed be He, had desired to make Chizkiyahu the Mashiach," linking it to the haftarah read on the last day of Pesach, which recounts his victory over Sennacherib.1 Other rabbinic commentaries reinforce that without singing a song of praise, the Messianic plan for him was not fulfilled.6 He remains noted as a viable Davidic candidate, though not exceptionally wealthy like some others.7