In last year's draft if they had a talented player, who was a cultural/character fit, that they graded higher on their board, but the position they played wasn't as big of a need, I think they'd take that player instead of Arnold. Example, in the 2023 draft many fans wanted the Lions to take a pass rusher/Edge or CB with their first, 1st round pick. Fans wanted Jalen Carter when he was sitting there for them to take and they traded back instead of drafting him. Once they traded back, Christian Gonzalez was sitting there for them to take, fans wanted him, and they went with Gibbs instead. I think they grade out their talent, ensure they are a culture fit, and rank them on their board.
Take Player A and Player B are being graded in the draft by the Lions front office and coaching staff. Player A and Player B play different positions. Player A is graded out by this organization slightly higher on their board than Player B is in-terms of overall talent + culture/character + scheme fit + need than Player B. Player B is still a very good player in the eyes of the organization and fits a need more in the eyes of most fans and pundits. However, Player A is ranked higher on their big board than Player B is and thus, I think they are sticking to their board and taking Player A over B, all things factored in.