Just because it never occurred to you to investigate the reasons atomic matter and structure even exist in the universe doesn't mean other people haven't investigated it.
That's got almost nothing to do with it.
Fine tuning is the framework of fundamental physical constants taking on invariant universal values, which if they all didn't converge on these precise values would mean atomic matter and structure would never have existed. I would add that the universe is curiously finely balanced between net positive energy and net negative energy, and without being balanced on this razor's edge the universe either would have flown apart so fast atomic matter and large scale structure wouldn't have coalesced, or the universe would have collapsed back in on itself within fractions of a second.