Saitama desired for strength manifested after defeating Crablante. That desired strength is to defeat any enemy in One Punch, Training for 3 years everyday without stopping while also fighting monster he find building a body that can handle his desired strength.
Saitama's supposed strength at 1 percent is always equal to any enemies 100 percent of their strength that's why he can defeat them in ONE Punch, if an enemy is above that percentage Saitama's power will rises up to be at equal again.
That's why there is no being that can rival Saitama's True Strength and Power alone as his potential to became even more powerful the stronger his enemies is.