title: Why dynamic languages don't guarantee the state of an object?
body: <p>I have come across the description of the memento design pattern:<br>
  <a href="https://refactoring.guru/design-patterns/memento" rel="nofollow noreferrer">https://refactoring.guru/design-patterns/memento</a></p>
  
  <p>At the bottom of the page in the <em>'Pros and Cons'</em> section, the author 
  states: </p>
  
  <blockquote>
    <p>Most dynamic programming languages, such as PHP, Python and
    JavaScript, can’t guarantee that the state within the memento stays
    untouched.</p>
  </blockquote>
  
  <p>Basically it says that if you do nothing with the Object(Mement) then the member(State*) can change? 
  Does this mean that the state of an object can change randomly? If so why?
  I am bit lost on this.</p>
  
  <p>*Dont confuse it with the 'state' I have used in the title.</p>