Protestants, you say that Catholics Worship Mary.
But what in this prayer to Our Lady of worship is it? Most of it is even taken from the Bible. "Hail Mary, full of grace, the Lord is with thee. Blessed are you among women and blessed is the fruit of thy womb, Jesus. Holy Mary, Mother of God, pray for us sinners now and at the hour of our death. Amen "
Virginia B is right. If you want to believe or not, when you pray to Mary, you are not praying to God and therefore the placement of Mary before God.
Mary was blessed above all women, but was a servant and no greater sinner than any other apostle or follower. Without grace, Mary would be as doomed as any of us.
Christ, through his work at Calvary, purchased the right for us to address God directly in their name.
Addendum
You are in error. If you ask me to pray for you, you are asking me to do so. Do not pray for me. There is a difference.
Mary was not sinless. Jesus himself said that all have sinned, and the height of the glory of God. Stating that Mary was sinless, ie that Jesus lied.
Your example is flawed. Not prevent sin (as suggested by the analogy). He saved like that saved all of us.
Finally, it was conceived without original sin, not Mary. Mary was conceived simply as any other human was.
Your question was about why the Catholic and Protestant view of Mary worship. The conclusion is that if you turn to someone other than God (Father, Son and Holy Spirit) for help, then you are worshiping to another entity.
There are numerous examples of this as a precedent in the writing. For example, when John fell before the angel who showed him the visions in Revelation, the angel rebuked him. While the angel was an agent or representative of God, it is clear that the prayer to God through the angel was rejected.
Of course this is all just fluff in the wind as far as Christianity goes. Mary's condition did not make a difference in the long term. Only Christ can save, and both Protestants and Catholics recognize this.
I disagree with both parts of the sentence: 1) "pray for us sinners now and at the hour of our death." I am a Christian and I believe that Jesus Christ is the one that makes intercession for us. Hebrews 7:25 - "It is also able to save the uttermost that come to God by him, seeing that ever lives to intercede for them." 2) It seems to give glory to Mary instead of Jesus Christ, who atoned for our sins. Dios te bendiga!