Just what does "easy to use" mean?
Easy to use is relative. To the user's experience, skill, culture, knowledge and environments. When stakeholders says easy to use, we need to be mindful of where they are coming from. The easiest to use nuclear power plant controls would be different from the easiest to use controls for a toaster. An easy to use tablet becomes completely useless in bright sunlight. A technical expert expects systems to speak their acronyms.
Easy to use is hard to do right. And impossible to perfect. Striving for easy to use its great, just don't expect it to be perfect for everyone. The easier something is to use, the more challenging the up-front work. And conversely, the harder something is to use, the easier (cheaper) the up-front work. Which explains why so many things made on the cheap are hard to use.
Easy to use evolves over time. It is a dynamic interplay between the design, and users' increasing proficiency/knowledge over time. Sometimes it is ok to let users learn something new, provided the longer term payoffs are worthwhile. Easy to use can become harder to use over time too as popular memes change - why does an odd little square mean Save?
Easy to use can be hard to measure and quantify. Especially if the user base is diverse. There is always someone who expects or wants something completely left of field - and sometimes with bloody good rationale too! Interestingly, depending on the task requirements, a broad group like "the general public" can be counterintuitively homogenous.
Easy to use is human-centric. It deals with emotions, behaviors, beliefs and expectations. It is more than just features, technology or visuals. Like social media, if you don't speak human, you can't do good user-centric design.
Easy to use is less ego, more service. Prima donna designers may not be so good at this service-attitude work. You really want the users to focus on what they are doing, not looking at the thing that is enabling them, and least of all to celebrity-worship the designer of the thing.
Easy to use means lots of user/people engagement. Lots of active listening. You have to be interested in people, in how they tick. All problems AND opportunities stem from people.
Easy to use requires saying no. Listening, understanding, empathising do not mean trying to please everyone Making decisions on what to include or exclude from the scope can be really hard, when you know how something will affect different users.