When the grumbling began in the wilderness of Sin, the Holy One responded not with rebuke but with a test. Targum Pseudo-Jonathan on Exodus 16:4 renders it: Behold, I will cause the bread which hath been laid up for you from the beginning to descend from heaven; and the people shall go out and gather the matter of a day by the day, that I may try them whether they will keep the commandments of My law or not.
Two striking additions from the Targum. First: the bread which hath been laid up for you from the beginning. The manna was not improvised in response to hunger. According to the Sages, it was one of the ten things created at twilight on the eve of the first Sabbath (see Mishnah Avot 5:6, compiled c. 200 CE), already waiting in heaven since <a href='/texts/bereshit-rabbah-1-1.html'>creation</a>. The grumbling triggered the delivery, but the provision had been there all along.
Second: the Targum tells us plainly that the daily rhythm was a test. That I may try them whether they will keep the commandments of My law or not. Not a test of their hunger, but a test of their discipline. Would they gather only what was needed? Would they trust that tomorrow's portion would come tomorrow? Would they rest on the seventh day and trust the double portion of the sixth?
The Maggid pauses on the word trial. A trial is not punishment. A trial is a weighing. The Holy One wanted to know what they were made of, and more importantly, they needed to know. Egypt had trained them to worry about tomorrow's bricks. Sinai was coming, and Sinai required a people who could receive a day's portion without hoarding.
Takeaway: sometimes the purpose of a daily limit is not to frustrate you but to retrain you. Manna in daily doses is a school for the kind of soul that can later receive Torah in daily doses.