What was the primary goal of redesigning the layout that resulted in the QWERTY arrangement?

Strategically spacing out commonly used letter pairs to prevent jamming.

The fundamental motivation behind the final QWERTY layout was strictly mechanical engineering: overcoming the issue of type bar collisions. The design objective shifted away from alphabetical order or operator ease and focused entirely on optimizing the machine's performance under stress. Engineers experimented to find arrangements where frequently used letter pairs were positioned far enough apart so that the mechanical arms had sufficient time to fall back to their resting positions after striking the paper. Therefore, QWERTY is fundamentally an anti-jamming sequence resulting from trial-and-error engineering meant to optimize the physical functionality of the early typewriter mechanism.