The best students on the French military schools in the Ancient Regime were destined for the artillery, the engineer corps or the navy. The second best students were assigned in the Cavalry and the Infantry, while the unable ones were dismissed. Already in 1782, Louis-Félix Guynement de Kéralio, impressed by the knowledge of the young Buonaparte in mathematics, wanted him to make a career in the navy. Following reasons were the cause than the young Buonaparte didn't enter the navy.
1° His mother Laetitzia was afraid of the dangers for his personal life as the French Navy had to fight mostly the English navy in wartime and lost in most cases those battles and the life on sea was always dangerous, even in peace time
2° the navy was very elitarist and accepted normally only officers from the higher nobility . As the Buonapartes were from the lower nobility this would have given him only small chances of being accepted and given the possibility for advancements. The artillery was in this circumstances the best option.

source : article by Gauthier Lamy - Gloire & Empire n° 80, september 2018, p. 24

Marc Moerman