An advertiser recently ran a month-long campaign on a new media platform. This campaign targeted customers who had purchased from the advertiser in…

An advertiser recently ran a month-long campaign on a new media platform. This campaign targeted customers who had purchased from the advertiser in the past year. Of the 10 million customers targeted, 3 million were reached. The average frequency for the campaign was three impressions over the month. The advertiser spent $100,000 on this media buy. After the campaign, an analyst from the media platform noticed that customers who received six or more impressions were twice as likely to purchase than those who received three or fewer impressions. To increase the number of users who receive six or more impressions, the analyst recommends that the advertiser double their spend. The goal is to increase the frequency from three to six in order to drive a significant increase in incremental return on ad spend. What primary concern should the advertiser's in-house measurement team have about this conclusion?