What is the purpose of a `transient do` block in FactoryBot factories?
<p>What is the purpose of <code>transient do</code> in FactoryBot factories?</p>
<p>I've seen a lot of factories that begin with something like below.</p>
<pre><code>factory :car do
  owner nil
  other_attribute nil
end
...
</code></pre>
<p>I've found some information on this blog:<br />
<a href="https://web.archive.org/web/20180403000920/http://blog.thefrontiergroup.com.au/2014/12/using-factorygirl-easily-create-complex-data-sets-rails/" rel="noreferrer">Using FactoryGirl to easily create complex data sets in Rails</a></p>
<p>But I still don't fully understand how and why to do this. My experience with FactoryBot is minimal.</p>
<p>Could anyone with some experience using FactoryBot share some insight?</p>