Explanation of the Limits of Earthlings' Battle Power

Because he is an Earthling, he is limited by his aptitude. In the original work, Krillin's Battle Power was 1083 when fighting Naba, and his maximum was 1700 (full power). Therefore, setting Krillin's Battle Power limit at 1500 does not conflict. At this time, Yueping's Battle Power is around 1400, so Earthlings have limited potential.

Namek Saga: His strength increased during the battle with Vegeta, and he also underwent mental training with Gohan on the spaceship for a period of time. Around 1500 (detected by Sabot's scouter).

After the Great Elder unlocked his potential: 13000 (official). His potential limit was increased to around 100,000.

Fighting Frieza: 75000.

Tenshinhan's Battle Power, on the other hand, is 1823. After all, Tenshinhan has the Bloodline of a Three-Eyed Human and is not a pure Earthling.

With this assist, Krillin can continuously break his own limits and eventually surpass Goku.