Did Kamikazee attacks achieve more than conventional attacks in their place would have?

And was it a good use of resources? Even if people were cheap, aircraft presumably weren't. These days military fighter aircraft cost in the millions of dollars. Even if they didn't cost as much back then, a fighter aircraft was still presumably an expensive thing to intentionally destroy. Did they have a surplus or something?

Did they have a surplus of people? Why not put these soldiers into conventional battle?

What lead to Japanese planners deciding on this strategy?