EXC_BAD_ACCESS when acess to property when object initialized by convenience init of superclass calling private init

I have some code here and when I call testFunc() it crashes on line value = NSObject() with error EXC_BAD_ACCESS (code=EXC_I386_GPFLT). I figured out, that removing private from class A init(_ object: Any?) fixes problem. Why does it happens?

class A {
    var object: Any?
    
    convenience init() {
        self.init(nil)
    }
    
    private init(_ object: Any?) {
        self.object = object
    }
}

class B: A {
    var value: Any?
    
    func test() {
        value = NSObject()
    }
}

func testFunc() {
    let b = B()
    b.test()
}