Because they must meet the strict requirement of being truly “holy”. Such people are quite rare. The only ones that can wear that title are those who are so very dedicated to God’s cause that they won’t even need the help of Christ’s kingdom to become holy. They will have achieved that standing during their life now. They, by reason of their holiness, will have already qualified for LIFE during their present lifetime.
So in effect, they will not need the ransom of Christ? Only the sinners, the unholy need Christ's ransom. The righteous have no need to be saved.
Is there truly a person anywhere who fits? Has there ever been? Not even Moses, David, or even Abraham fit that. They STILL recognised their need for Christ's ransom, they were considered righteous, but they all knew they were not without sin.
The fact is ALL need the help of the kingdom, ALL need to drink of its water to have life. One cannot have life without drinking, one cannot have life outside the kingdom.