I think it's because of the lack of career growth. I have personally seen many such cases when it is easier for the owner of the company to hire a new employee than to allow someone who has been working for a long time to expand the duties and, accordingly, the salary
	
		
			
		
		
	
				
			 
 
		 
			
		
		
		
	
	
			
		 
			
		
		
		
	
	
			
		 
			
		
		
		
	
	
			
		 
			
		
		
		
	
	
			
		 
 
		 
			
		
		
		
	
	
			
		 
			
		
		
		
	
	
			
		