Saucy subject lines seduce subscribers: ‘Lust’ trumps ‘love’ in email marketing

Mar 7, 2013 | Online advertising

This year’s Valentine’s day email campaigns have produced some eye-opening stats, with subject lines without discounts performing better than those offering a discount, and ‘lust’ getting higher clicks than ‘love’. Guy Hanson, Director, Response Consulting at Return Path looks at reasons for these anomalies, and provides some top tips for email marketing seasonal campaigns. Email […]

This year’s Valentine’s day email campaigns have produced some eye-opening stats, with subject lines without discounts performing better than those offering a discount, and ‘lust’ getting higher clicks than ‘love’. Guy Hanson, Director, Response Consulting at Return Path looks at reasons for these anomalies, and provides some top tips for email marketing seasonal campaigns.

Email marketers whose programmes have a strong seasonal element – such as Valentine’s Day – have to deal with conflicting objectives as these events approach. It’s their big opportunity to chase sales, and in doing so established email marketing best practices often fly out of the window. This can impact negatively on email deliverability, which has two broad elements:
Sender Reputation: Like a credit score for email marketers, reputation metrics serve as a barometer for the overall health of your email programme. Factors such as spam complaints, data quality, broadcasting infrastructure, and IP address permanence can increase/decrease this score, which has a straight-line relationship with Inbox Placement Rates.
Subscriber Engagement: ISPs also consider the interactions (positive and negative) that your customers have with their emails. Retrieving wanted emails from a spam folder, or forwarding an email is regarded as positive. Registering spam complaints, or deleting emails without reading them, are negative behaviours.
Sender Reputation and Subscriber Engagement determine whether your emails get delivered to your subscribers’ inboxes and where they are being placed.
These principles can be illustrated by looking at the email programmes run by some of the UK’s best-known lingerie brands. Lingerie lends itself perfectly to Valentine’s Day email marketing, with many men preferring the anonymity of being able to purchase lacy surprises online. From an email marketing perspective, this can lead to some unintended consequences as can be seen from the following chart, compiled using aggregated data from Return Path’s Inbox Insight email intelligence solution:
Outside of seasonal windows, the average UK lingerie brand sends slightly more than 3 email campaigns per week. From our data we can see that this almost doubles in the fortnight before Valentine’s Day.
Unsurprisingly, we can also see that ISP Spam Filtering rates for these senders also increase sharply during the corresponding period. There are several common reasons for this:
• Brands are more likely to email disengaged subscribers (who complain more) during this period
• Greater competition in the inbox for eye-share
• Increased subscriber fatigue because of email overload
• Reduced relevance as email marketers concentrate on volume, rather than targeting and segmentation
A Test and Learn Approach
To deal with these factors and minimise their ISP spam rates, email marketers need to demonstrate greater understanding of customer needs, and apply targeting and segmentation strategies that reflect this. Email is the perfect medium for test-and-learn programmes, and we have seen some excellent examples of retailers using this approach over the past fortnight:
In this example from Ann Summers the comparative effectiveness of two subject line keywords – ‘Love’ and ‘Lust’ – is measured. The majority of respondents are clearly sinners at heart because ‘Lust’ comes up trumps, delivering higher Read Rates, and lower ISP Spam Filtering rates.
This campaign from La Senza considers the effectiveness of subject line discounting. Interestingly, the subject line without the discount (but possibly the more emotive content) performed better, with Read Rates a full third higher and ISP Spam Filtering rates lower by a third.
Lovehoney provided additional insight into the impact of subject line discounting with one set of subscribers receiving a ‘50%’ discount offer and the other receiving a ‘75%’ discount offer.
Perhaps counter-intuitively it was the smaller discount that generated much higher Read Rates, and much lower Deleted Unread rates. A potential reason is that subscribers are naturally cynical about promises of huge discounts. An alternative explanation is that this was a ‘recency-based segmentation’, meaning that older and therefore more disengaged subscribers were provided with a bigger offer in the hope of re-activating them.
Know your Audience
One of the most intriguing Valentine’s email that we saw was also one of the more unexpected ones. Time Out London snuck out a positively racy email titled “After-dark fun: open if you dare!”
Subscribers who opened the email might be forgiven for being startled as they digested 50% off deals on a “Bikini, Brazilian or Hollywood Wax”, a “Couples’ Boink Box”, and even an “Ooh La La Rabbit Vibrator!” The accompanying editorial proudly advised readers that “After repeated ups and downs, Time Out’s sex issue has finally arrived. Consummate the occasion with tonight’s special offers!”
Marketers need to be 100% confident of knowing their audience when they try an approach like this because of the high risk of offended subscribers voting with their spam buttons. Fortunately, the engagement metrics show that Time Out targeted the campaign in the right way. The following graph shows Read Rates were up almost ten percent against their 30-day benchmark, while Deleted Unread rates reduced significantly. ISP Spam Filtering rates did increase slightly, but did not impact materially on overall campaign responsiveness.
Top Tips for Subscriber Success
So with more seasonal events such as St Patrick’s Day, Mother’s day and the Easter holidays coming up, what should email marketers be doing to make sure that their programmes are equipped to deal with these challenges?
• Ensure your programme is generating a top-drawer set of Sender Reputation metrics. Programmes with high scores perform better during these periods of increased activity. Check yours at
• Make sure you are mailing to highly engaged subscribers. Relevant and targeted offers generate higher Read Rates, leading to more conversions and greater ROI.
• Provide subscribers with meaningful choices about what types of emails and offers they are sent, how often and at what time they receive them, and on what devices.
• Ensure you can measure the same metrics that major ISPs are using to determine whether email subscribers are engaged or not.
• Get certified to benefit from reduced volume throttling restrictions, automatic image enablement, and preferential treatment from major spam filters.
Email marketing programmes that have these bases covered will benefit from better deliverability, increased responsiveness, and greater conversion to sale during these red letter periods on every marketing calendar.
• Aggregated data was taken from: Agent Provocateur; Ann Summers; Bouxavenue; Figleaves; Lovehoney and La Senza.
• All comparative analyses were based on email broadcasts that took place on the same day, and using panel sizes of similar proportions.
• To avoid presenting commercially sensitive data, all values have been presented as indices, with the benchmark performance being shown as 100, and the uplift performance then relative to the benchmark.
For example, if message 1 achieved Read Rates of 15% and message 2 achieved Read Rates of 20% these would be shown as 100 and 133 (a third greater than the benchmark) respectively.
By Guy Hanson
Director, Response Consulting
Return Path

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