The title determines the user's decision: to go to the page, open the product, read the article, or ignore it. The effectiveness of headlines is measured through A/B testing. The one that gets the most clicks wins.
If a user clicked on a headline and then left the site in a split second, returning to the SERP or to the previous page, can we assume that the headline worked?
The effectiveness of headlines should be measured not by the CTR level, but by the user engagement on the page.
The theme is a key conversion element, the tasks of which are:

Effective headlines create interest and motivate you to move further along the website page.
By attracting the user's attention, the title determines what background knowledge is activated in the person's mind to perceive the material. The title determines where your attention is directed when reading.
Headlines help search engines decide whether our offerings match what users are looking for. Most search queries are two to four words long and consist of proper nouns and keywords. The best headlines will match the most common relevant search queries. Here are some guidelines for choosing words.
If you are interested in this topic, you can read more about it in “Solutions”.