You should segment your audience before you start a marketing campaign. This is because studies show that people are more likely to appreciate and engage with brands that take the time to personalise their campaigns with dedicated offers that have been created for them.
The more often you go through the campaign segmentation process, the better you will know your customers. Then, the better you know your target customers, the more personalised your campaigns will become. This means you will stand a much higher chance of your campaigns returning a favourable, cost-effective outcome.

Plus, you should also remember that campaign segmentation is an evolutionary process. After all, as people grow up, change jobs, and move house, they will move between segments. Due to this, you need to continually review your segments to ensure they’re up-to-date and monitor how people are moving between segments. If not, you’ll be making marketing decisions based on inaccurate data.