The job this tool does, and who does it today
Most leads are not lost to a competitor. They are lost to silence. Somebody enquired, was contacted once, did not answer, and was never contacted again because the person who owned that lead had thirty other things happening that week.
The work of fixing that is design work, and it happens before any software is involved. Today it usually does not happen at all. Follow-up is described in a team meeting as call them twice and send a WhatsApp, and each rep interprets that differently. A few teams write it on a whiteboard. Very few write down what should happen when the prospect says not now, which is the most common answer of all.
A follow-up sequence planner is where that design gets written down: touch by touch, with a day, a channel, an owner, an intent and an exit rule.