I believe that leaving your place of employment simply because you don’t feel praised or recognized for your effort is understandable, but not a great reason. It’s not about trying to get recognition because the work you are doing is about helping the company benefit the customers, who are the people. You, personally, should praise yourself first and foremost by telling yourself that there are others who are not willing to do the work you are doing or simply are not as bright as you to be able to do it so well. Looking for praise and recognition is not something that should be emphasized. The results of your own work is it’s own reward. At times the employer may dismiss the hardship that you endured, but then again, the employer chose you for that person out of all the others that applied so it’s not like the employer doesn’t see you as valuable to his/her business. I think that this is not related to the second reason, which is exciting and challenging work because this is somewhat subjective. What you consider to be challenging may be different than what someone else thinks is challenging. It’s only challenging when you don’t know it, but when you know what to do through experience and education, then it’s not hard at all. It may still be a lot of work that you have to do, but knowing is half the battle. So I don’t think that these two reasons are correlated with each other.