I would say, the more senior and older you become the harder it is to find a new job. Location can be key too, in the UK. Technical tests are a subjective nightmare. I'm fairly sure, after god knows how many interviews, a decision has been made on you, in the foyer, before you've even answered the first question. You've just got to keep plugging away at it and don't ever let the interview process undermine your confidence as developer. On that note, confidence in your own skills, knowledge and experience is a crucial factor in being a successful developer. Also note that every job will fundamentally change in some way within the first six months. For example, in my current role, my original line manager retired within two months.