The best way to follow-up with someone - and the most effective way to do so - even if this turns out to be the last time you speak with this person as a potential client or customer for what you offer, is to have a specific appointment or agreed upon time for the next contact. This way when we call that person, we don't have to be concerned about how they feel about us contacting them.
Without a specific time and date for reaching out to them again - even if they forget about it or aren't ready to speak with us - we run the risk of annoying them, bothering them, appearing too pushy or forward, trying too hard to make a sale, or worrying that they will think poorly of us for contacting them again so soon after our last conversation. However, if we wait too long, as many salespeople do, we risk them forgetting about our conversation and having to re-introduce ourselves to them.
Therefore, always get an agreement from the people we are calling or visiting in-person again for a specific time for that to occur. This is done before concluding the initial meeting, presentation, or conversation.
The next best way to have a good outcome from a follow-up contact is to make sure the people we are reaching out to again have more than a passing interest in what we discussed with them. If we contacting someone again with no reasonable interest in us or what we provide, the chances of a successful second conversation are slim. They won't be particularly happy or impressed, and neither will we.
Someone should at least be able to purchase what we offer and be interested enough in it and us to want to speak with us again. Otherwise, follow-up is just an activity that is done and not one that advances the sales process.
Far too often, salespeople (or any product or service) will telephone or email someone after the initial meeting or presentation without any real basis for doing so. Many time, they will restate their case - when there was no real interest in purchasing anyway. Sometimes, they will emphasis a point that their company or they want stressed without regard for what the consumer might be focusing on or interested in the most.
Salespeople typically start off a follow-up conversation by asking if there are any questions. When there aren't any, they either hang up - wasting a great opportunity to engage their customer again - or they start in with a generic sales presentation again that is not tailored to the person's needs they have called.
A classic greeting for salespeople to use is telling the person they are contacting that they are "just following up," "checking in," or "touching base" - none of which matter to the person they are calling and certainly doesn't start the conversation on a positive note.
Finally - for now, because there are many more weak and unsuccessful follow-up techniques that we could look at - salespeople keep contacting people long after they have made it clear they have little or no interest in moving forward. Salespeople feel that they just need to be more persistent to change their minds so they keep at it. Only instead of being persuasive, they just push the person further away from them and remove any possibility of ever doing business.