Love is the greatest motivator.  Even when it seems that nothing can be changed, love still wants to do whatever can be done.  The women who had followed Jesus from Galilee were helpless and hopeless after His death.  Nevertheless, they did what they could.  They had stayed by the cross, had seen all that happened to Him and heard His words (Luke 23:48-49).  They knew that He was dead.  They saw the soldiers' final act of physical abuse and waited until His corpse was taken down from the cross.  Then they followed Joseph of Arimathea, not letting the body of Jesus out of their sight. They formed an uneasy procession following Joseph and Nicodemus as they laid Jesus in the new family tomb which had been prepared for Joseph himself (John 19:38-41).
 
Having seen the sacred body laid to rest and the tomb sealed, these women quickly went home to prepare additional embalming spices.  However, the Sabbath was soon upon them at nightfall on that first Good Friday, preventing them from doing any more work.  And so they rested on the Sabbath.  But they had no idea of what God was doing behind the scenes.  Although Jesus had explained at least three times that He would be put to death but would rise on the third day (Matthew 16:21; Matthew 17:23; Matthew 20:17-19), neither the disciples nor the women understood.  

But Father God had been preparing the women for a crucial role in the crucifixion/resurrection event.  The women saw it all.  After the disciples had gone away, the women had seen the body being taken from the cross, embalmed with spices and carried by Joseph of Arimathea and Nicodemus to the rock tomb.  They could validate which tomb Jesus was in because they sat and watched His body being placed there (Matthew 27:59-61).  They would become the witnesses of the empty tomb and first to announce the resurrection because they were also the first to see the risen Jesus (Matthew 28:1-10).  Their love put them in the right places to become crucial witnesses, proving that Jesus did die and that it was His body in the tomb.  Their careful and continuous observation enabled the Gospel writers to establish the truth of His death and the credibility of the resurrection.  They were given that role because they persisted in their love for Jesus.
 
We should not be surprised that God uses our little acts of faith for His own purposes. "... we know that in all things God works for the good of those who love him, who have been called according to his purpose." (Romans 8:28).  Whenever people act in faith and love towards the Lord, He moulds their contribution into His greater plan.  Like the Old Testament prophets, those He uses hardly ever understand the full impact of what will be achieved (1 Peter 1:10-12).  They simply step ahead in faith and do what they can.  So, it is best not to try to second-guess what God will do; but to simply express faith, love and obedience in the best way we can - leaving Him to complete the picture so that He gets the glory.