I found this question in one of the groups related to website development, and I really enjoyed reading the answers, which were largely accurate and logical. Unfortunately, I did not find in them the answer I was waiting for, which reflects a conviction that has been ingrained in me over about 16 years of professional experience in web development and digital marketing together. This conviction might be absent in many software developers due to their lack of managerial and marketing background.
For me, the most crucial factor for the success of a website is that it serves the intended purpose and provides a user experience suitable for that purpose. It is not a requirement for it to be simple and without complexity.

Why do you want to create a website?

This is the first question I ask my clients in our initial meeting or call, not what features and characteristics they want their site to have. If the client does not have a clear vision of why they want a website, they will not be able to determine the appropriate features and characteristics for their needs.
The website could be your virtual office, your store, your school, your meeting room, or anything else that is a digital reflection of some activity. It allows you to engage in this activity remotely and everywhere, 24/7. Of course, not all activities are the same, and they have different needs. The determination of features and related operations depends on defining the purpose or purposes of its existence.

What features should be present on the website?

After reading the comments on the posed question to understand the trends of opinions among website developers, I found that the answers can be summarized in some points. Of course, all of them are important, but their importance and how to achieve them fundamentally depend on the purpose of creating the website.

1. Good Design:

   Good for whom and why? Design is considered one of the most challenging factors to measure on any website because design, in general, is highly subjective, varying from person to person. There cannot be universal standards to judge the quality of design without considering the purpose of the design. For example, if you want to create two websites for children aged 4 to 7, targeting the same audience, but one is intended for displaying cartoon stories and the other for educational lessons, it is inconceivable to use identical designs. The purpose always dictates the design. The term "good design" alone cannot be a readily applicable and measurable criterion. It can be articulated as a design that is good for a specific purpose and its targeted audience, possessing certain characteristics.
   Identifying the target audience and its characteristics is one of the most important elements to consider. Even color connotations differ from one culture to another. Some cultures perceive red, for example, as the color of death and blood, while in other cultures, the same color represents life, joy, and happiness.

2. Compatibility with Search Engines:

   Indeed, compatibility with search engines is important for some websites, but it cannot be crucial for all websites. Simply put, the purpose of building a website may require hiding it from search engines as part of securing it against hacking attempts. For instance, if I am developing an application for managing accounting and administrative operations for a company, and I want this site to be accessible only to the company's employees, there is no reason to make it compatible with search engines. In this case, I would include code in the robots.txt file to hide the site from search engines because, in this scenario, part of its security requirements is to remain concealed.

3. Security Against Hacking:

   Securing the website is undoubtedly a very important factor to consider when developing a website. However, not all websites need security to the same degree. The answer also lies in the purpose of the website. It is not logical for a client with a small website showcasing basic company information to request a security plan that costs ten times the price of the website itself. Security measures should align with the nature of the website—whether it is a simple informational site or an e-commerce platform where users engage in buying and selling with electronic transactions. The security requirements for each should be proportionate, and a separate budget should be allocated for security considerations.
   In the end, you'll find that the purpose of creating the website is the primary determinant of the security factors.

4. Speed:

   The responsiveness of a website is also a relative factor depending on the content and, therefore, the purpose of the website. A fixed speed cannot be determined to measure any page on the internet; it is relative and can vary. We might not tolerate a small site displaying information about a store or company taking one second to load and yet consider a bank's website taking more than a minute for a transaction acceptable. It is highly subjective, and a fixed ideal time for loading web pages cannot be set.

5. Compatibility with Various Screen Sizes:

   Like all the previous points, the importance of compatibility with different devices stems from the purpose of creating the website. Naturally, a company's data display website should be compatible with all devices to provide a distinctive user experience. Also, it needs to be compatible with search engine standards. On the other hand, if I want to develop a site used by accounting employees from desktop computers, and resizing screens to fit small mobile phone screens would hinder the proper display of accounting tables and menus, there is no need to create a site compatible with small screens.

In conclusion, before considering any website features and implementation methods, it is crucial to understand the purpose of the website to determine how to build it and how to define its components.