From a personal experience, having a portfolio has given me the credibility for opportunities I have sought out. It has also granted me my current position and responsibilities – whether it was because I had solid representation of the skills acquired through previous internships or simply the confidence that came with seeing all the work I had done in the past.
One of the best advice I have gotten from a supervisor was that they love the trait “organized.” Being so organized that if I person had to take over my job at any given moment, they could pick up exactly where I left off – assuming they had the same skill set. Bringing a portfolio was living proof of such organization & marketing trait.
And even if you land your dream job, keep collecting because you never know what could happen. I don’t mean this in a negative way. You might grow out of your position and dive into the interview process again for management positions. You might start a family and need a closer commute or more flexible hours or have to suddenly move. It is always good to aim for stability in your jobs, but also remember that it is also a representation of your own skill set. Treat it well and collect your proudest accomplishments.