Torpedo boats did not disappear once torpedo-boat destroyers acquired torpedoes of their own. The smaller craft remained useful within flotillas and for coastal defence. Destroyers developed the reach and seakeeping needed to accompany fleet operations. The distinction explains how the two related types could continue along different operational paths.
Notable Point · 1:41:46-1:42:10
Torpedo boats stayed with coastal defence
A follow-up separates the local defensive role retained by torpedo boats from the fleet operations taken on by larger destroyers.