Getting a stubborn seam to meet is mostly about how you take it apart and prepare it, not about stitching harder the second time. When a join refuses to line up, unpick it from the front rather than the back. Patchwork seams carry no knots or backstitching at their ends, so the stitches lift out cleanly from the right side, where you can see exactly which ones to cut and stop the moment you have opened enough.
Be sparing about what you open. If one intersection has already come out beautifully, leave it be and unpick only the seams on either side of the one that went wrong. Then take out every loose thread and press the exposed edges flat before you try again. The creases pressed in by earlier attempts are usually the very thing standing between you and a clean match, and a freshly pressed edge will sit down where a tired, twice folded one simply will not.
Before you commit to it, baste. Run a long stitch through the intersection inside the seam allowance, open the work out and check that the points genuinely meet. If they do, sew it properly over the top and enjoy the moment. If they do not, only the basting has to come out, which takes far less time than unpicking a finished seam and beginning the whole dance over again.
Where do you draw your own line between basting a tricky join first and sewing it straight off and hoping for the best? I would love to hear how you handle the seams that fight you.
