The text discusses the use of custom domains for link tracking in text messaging to improve user experience and ensure message deliverability. It highlights T-Mobile's preference for using one recognizable domain name and their rules against URL cycling and multiple redirects. To improve delivery of messages with links, it suggests limiting the number of redirects, using full-length URLs when necessary, and employing branded shortened URLs instead of public link shorteners. The article emphasizes that maximizing message deliverability is in businesses' best interest as they pay for all sent messages, not just delivered ones.