Is it worth rotating between the Magnificent 7, or is it better to just never sell?

Let’s say you own several Mag 7 stocks and one of them has gone up significantly, leaving you with a 30%+ unrealized gain. At the same time, another Mag 7 company has dropped considerably and you believe it has become undervalued relative to the others. Would it make sense to sell some of the stock that has performed well and rotate that money into the one that looks undervalued? Or, assuming you have a long-term horizon, is it generally better to simply hold your positions and avoid trying to rotate between them? Right now I’m up around 80% on GOOG and 40% on MSFT, which is what makes me question whether rotating into another undervalued Mag 7 stock would actually be worth it or whether I should simply let the winners run. My thinking is that once a position reaches a 100% gain, it only needs to rise another 50% from that point for my original investment to reach 3x, and the percentage increase required to add another multiple of my initial investment keeps getting smaller as the position grows. So I’m wondering whether giving up that accumulated position to rotate into something cheaper actually makes sense, assuming I still believe in GOOG and MSFT long term. I’m curious whether anyone here follows this kind of strategy with the Mag 7 and how it has worked out compared with simply buying and holding. Thanks!