The British political situation was such that they did not want to hear what was true, that they did not have a strong enough force to hold Crete. Freyberg communicated this message to the government of New Zealand. We suspect that the real problem was Churchill. Wavel was a "team player" who could not tell Churchill that he could not do anything. This is the thinking that made the Greek operation a disaster, which lost Crete, and almost lost North Africa.
General Wavell praised the New Zealand Division performance in Greece and told Freyberg that he expected an attack in a few days, and that he wanted Freberg to command the defense. Freyberg later wrote that he did not know about the Crete geography the "characteristics of the island" or the nature of the defending force. The commanders did not know a realistic assessment of the attacking force.
To fix the problems, it took having Alan Brooke as the Chief of the Imperial General Staff and Bernard Law Montgomery as the 8th Army Commander. "Everyone hated Montgomery", but he could win battles. Alan Brooke was the one who recommended Montgomery to Churchill. This is based on the account in "Greece Crete and Syria" by Gavin Long.