Q. In a recent answer you criticised current Bar-Mitzvah procedure. But are not Maftir and Haftarah obligatory?
A. The answer is no. Nowhere in the Bible is there any reference to Bar-Mitzvah or to a Bar-Mitzvah ceremony. The name appears in rabbinic literature in relation to any Jewish adult male obliged to observe the laws of the Torah. This obligation begins at 13; Pirkei Avot 5:24 says, “At 13 (the age is reached) for the fulfilment of the commandments.” The Midrash acknowledges that 13 is usually the age when one is mature enough to make decisions (for girls the age is 12); thus at 13 Esau opted for idolatry and Jacob for Torah (Gen. R. 63:14).
Not until about the 8th century was there a form of ceremony to mark the age of 13; the late tractate Sof’rim (18:5) states that a boy of 13 is taken to the elders for a blessing and a prayer that he may merit to learn Torah and do good deeds. One version of this passage actually calls the boy a Bar-Mitzvah. By the 14th century in Germany there was an accepted Bar-Mitzvah ritual; the Shulchan Aruch takes it for granted that a Bar-Mitzvah is called to the Torah and there is a festive meal and a discourse (Orach Chayyim 282; Magen Avraham ad loc.). But there is no absolute requirement that when a Bar-Mitzvah is called to the Torah he should read Maftir and Haftarah, and this is not the universal custom.
In my view, as my earlier answer indicated, it takes so much time and effort for most boys to learn Maftir and Haftarah that the time would be better spent in getting the boy thinking about Judaism as a whole and preparing a D’var Torah that gives voice to his own thinking.