In the Parable of the Sower and Seed, aka the Four Soils, Jesus touches on not one but two of the Conundrums of the Faith - those really tough questions that make one wonder how God can be loving, just and omnipotent.
First question: in a universe ruled by a loving God, why does he allow dreadful things to happen to people?
Note the explanation for the Rocky Soil - the believer with no roots who withers when afflicted by scorching trials. So flip that around - let's say a plant instead has sunk deep roots into good soil and is drinking good water. Does the sun still wither it? No - in fact, sun is essential to its growth. In the same way, the trials that would wither a believer without roots are actually essential to healthy growth in the believer with roots sunk deep into the Word and drinking from the springs of Living Water. As sunlight is a catalyst for growth under the right conditions, trials are an opportunity to trust the Word and rely on the Spirit.
Second question: does God want everyone to be saved?
In his explanation of why he speaks in parables, Jesus seems to answer the above question with a flat no. He seems to say that the Kingdom is meant for some people and not for others: "the knowledge of the secrets of heaven has been given to you, but not to them."
But upon reading the rest of the chapter, which is all about who makes it, who doesn't, and why, I hear him saying something like this: People make their own choices, and thus are their own judges. The person who won't make a token effort to understand a parable of Jesus doesn't have a Kingdom-seeking heart. Parables are like the shepherd's call: if you are ever hearing, understanding and responding, that's how (or at least one way) you know you are a sheep of his flock and under his protection. "My sheep know my voice."
God sovereignly chooses us, the sheep of his flock. In his inscrutable wisdom he allows us to choose Him also. I still don't "get it", but in the pages of the Bible, from beginning to end, mankind is asked by God to choose Him. The message is insistent and I must believe our ability to respond, or not, to God's calling is no mirage.