About 3-4% of appeals are dismissed on technical grounds. But in addition to that, many more go through full briefing on the merits, but still ultimately fail on technical grounds. Here is an appellate effort that failed for purely technical reasons. Ghannoum v. Sevier (D2d2 Apr. 7, 2021) no. B304026 (unpublished). (The court also clearly was not excited by appellant's arguments.)
Ultimately, a loss is a loss. But one wants to avoid losing by way of all arguments being deemed waived.