The first thing the servant is asked
إِنَّ أَوَّلَ مَا يُحَاسَبُ بِهِ الْعَبْدُ يَوْمَ الْقِيَامَةِ مِنْ عَمَلِهِ صَلَاتُهُ، فَإِنْ صَلَحَتْ فَقَدْ أَفْلَحَ وَأَنْجَحَ، وَإِنْ فَسَدَتْ فَقَدْ خَابَ وَخَسِرَ
Inna awwala ma yuhasabu bihi-l-abdu yawma-l-qiyamati min amalihi salatuh, fa-in salahat fa-qad aflaha wa anjah, wa in fasadat fa-qad khaba wa khasir.
"The first deed for which the servant will be judged on the Day of Resurrection is his prayer. If it is sound, he has succeeded. If it is corrupt, he has failed and lost."
Narrated by Abu Hurayrah. Jami' at-Tirmidhi 413
A short reflection
Order matters. Prayer is the first check. If the foundation passes, the rest is examined. If it fails, everything else is wobbling on nothing.