Does God have the POWER to keep his creatures from falling into sin? Of course.
Was it God's PURPOSE to prevent the fall? No.
Yet this does not mean God was not grieved by the fall.
Does God have the POWER to save all people? Certainly.
Is God's PURPOSE to save all? No.
Yet this does not mean God does not desire the salvation of all.
Is there sufficient POWER in the atoning work of Christ to save all? Absolutely.
Was this God's PURPOSE in the atonement? No.
Yet this does not mean the atonement is inherently limited.
Does God have the POWER to move every living person to repentance and faith? Certainly.
Is it His PURPOSE to irresistibly draw every living person? No.
Yet the fault for the sinner's unbelief lies with the sinner alone.
Does God have the POWER to keep Christians from sinning? Yes.
Is it God's PURPOSE to make us sinless in this life? No.
Yet we are responsible to grow in grace, mortify sin and persevere in faith.
I have just explained why I am a 5-Paradox Calvinist.
Here is R.C. Sproul with a few thoughts on God's sincere desire for the salvation of all.