Jesus used parables to connect with the ordinary lives of people.  They would understand the situation Jesus described, and then some would be intrigued to find out the deeper meaning.  Everybody was familiar with farming.  Food production was the principal element of the economy in Jesus' day, from fishing in the sea to sheep farming on the hills and harvesting crops from the flatter areas.  Sowing seed was not mechanical but by the farmer throwing out handfuls of seed-corn from a basket by hand.  The skill was to get the right amount of seed in the right places.  So Jesus described the types of land which would be unproductive, as well as the premium areas of good, deep, well-watered soil.
 
Those agriculturally-aware people would have agreed that the only soil which would produce a return on investment was the good soil; and that stony or weed-infested land would never make money or feed the family.  They would have recognised how the seed might be carried away by the flocks of birds following the sower, and how the poor soil would not have enough water.  But the crowds could not understand the meaning of the parable, nor could the disciples (Matthew 13:10).
 
They knew it was a riddle of some kind (a much-loved style of Eastern communication).  Jesus wanted the disciples to be hungry to find out the hidden meaning (Matthew 13:11-13).  In fact, the story was really intended for them.  It was a part of their training course in becoming apostles.  They needed to understand about the different types of spiritual response they would encounter as they preached the gospel, so that they would not get discouraged but keep on sowing the seed of the Word of God.
 
We are all on God's training course.  He is teaching us through the parables of life how to receive His love, be useful in His Kingdom and be prepared for heaven.  Often, we will not understand what God is doing and assume that the strange events of life have no significance; they are riddles to us.  But He is drawing us to ask Him to teach us through them.  True disciples will ask the Lord to reveal what may seem obscure.  He will illuminate our hearts as we listen to His Word and ask Him to explain it to us.  Then we will be able to help others.