Voadam
Legend
Close.Even old-school D&D had prime requisites. Roll under a 15 strength? You can't be a fighter, period.
As others pointed out 1e AD&D said a character generally should have at least two 15s to be survivable but did not specify where and specifically set the minimum bar at a 9 for a fighter. Worth noting Gygax's phrasing is not that you need two 15s to play the character.

"Each and every character has six principal characteristics, the character’s abilities. These abilities are strength, intelligence, wisdom, dexterity, constitution, and charisma. (See also APPENDIX I, Psionic Ability.) The range of these abilities is between 3 and 18. The premise of the game is that each player character is above average — at least in some respects — and has superior potential. Furthermore, it is usually essential to the character’s survival to be exceptional (with a rating of 15 or above) in no fewer than two ability characteristics."
STRENGTH TABLE I.
Ability Score General Information
3
4
5 Here or lower the character can only be a magic-user
6 Minimum strength for a gnome, half-orc or halfling character
7
8 Minimum strength for a dwarf character
9 Minimum strength for a fighter character
10
11
12 Minimum strength for an assassin or paladin character
13 Minimum strength for a ranger character
14 Maximum strength possible for a female halfling character
15 Maximum strength possible for a female gnome character, minimum strength for a monk character
16 Maximum strength possible for a female elf character
17 Maximum strength possible for a female dwarf or female half-elf or male halfling character
18 Maximum strength possible for all non-fighter characters
18/01-50 Maximum strength possible for a female human or male gnome character
18/51-75 Maximum strength possible for a male elf or female half-orc character
18/76-90 Maximum strength possible for a male haIf-elf character
18/91-99 Maximum strength possible for a male dwarf or male half-orc character
18/00 Maximum human strength
2e had no such recommended minimums and in fact under stat generation method I it says explicitly to expect mostly 9-12 scores.
"Method I: Roll three six-sided dice (3d6); the total shown on the dice is your character’s Strength ability score. Repeat this for Dexterity, Constitution, Intelligence, Wisdom, and Charisma, in that order. This method gives a range of scores from 3 to 18, with most results in the 9 to 12 range. Only a few characters have high scores (15 and above), so you should treasure these characters."
In B/X you generate stats like in 2e method 1, 3d6 in order but you can lower some stats to raise your class prime requisite giving up two stat point increments to raise up one point increment within certain boundaries.