When personal suffixes attach to weak-final perfects, the surface ending changes.
Word / formMeaning / explanation
دَعَا → دَعَوْتُhe called → I called; underlying wāw becomes visible with the suffix.
رَمَى → رَمَيْتُhe threw → I threw; underlying yāʾ appears with the suffix.
رَضِيَ → رَضِيتُhe was content → I was content.
These forms show why a final alif in one inflection should not be treated as a permanent original alif radical. Other suffixes may expose the actual weak consonant.