Hire people (on good money) with the personality type that likes to find problems. If the team is all composed of "Mr Right-Now" and no "Mr Right" personality types then it will move very fast and have lots of issues. A diverse team helps.

TDD tries to insist tests are developed first, partly to ensure they're not skipped.

Reinforce the message: "Measure twice, cut once".

Good leadership and top-down support to make changes are important. If they won't care enough to stump up the money and follow through to check it's happening, don't expect much change.