Twig array access

I'm trying to print out value of the variable passed to the twig template. I'm using this code:

{{ naziv[0] }} Index is 0 because passed array has only one element. Mentioned code produces following error:

Key "0" for array with keys "title" does not exist in...

but when I use for loop like this:

{% for key,value in naziv %}
{{ value }}
{% endfor %}

I get what I want.

What's wrong with {{naziv[0]}} ?