First, God created us to have free agency, making our seeking Him and a relationship with Him the more precious
Second, God does not intervene in all tragedies because to do so would make God 'manipulatable' and thus not God as we have been taught to think of Him; reacting to the actions of others everytime makes you slave to their actions; put another way, God cannot be tempted
I hope that helps ...
But hasn’t there been supposed cases where he did intervene and lead people to find Him even when they were not looking for Him? Why doesn’t he let everyone in the world know that the should be looking? Until I was about 23 or so God never intervened in my life and never even tired to let me know that i should be looking for him. At 23 I feel He may have picked that time to intervene, but I don’t know why He would wait that long.