Mistake 1 — Launching the campaign in August or December
This is the most common mistake, and the most expensive. Launching a 6-month CGE survey in the middle of August means burning the first email — the one with the highest potential open rate — on alumni who are on vacation, in transit, or simply disconnected from their inbox. December is even worse: end-of-year reviews, season's greetings, and the noise around the holidays saturate inboxes.
Based on our field observations, launching in August vs April on the same cohort costs 10 to 15 points of final response rate. December costs 8 to 12 points. What makes it so brutal is that the loss can't be recovered through reminders: an alumnus who didn't open the first email is less likely to open the following ones.
Antidote. Launch the 6-month campaign between mid-March and early May. Launch the 30-month campaign between mid-September and mid-October. For the full timeline, see our month-by-month CGE survey calendar 2026. If you're constrained (late back-to-school, team tied up with other campaigns), shifting by 2-3 weeks is better than sending "on the wrong date".
Mistake 2 — Sending a questionnaire of 25 questions or more
The instinct is understandable: "as long as we've got them, we might as well ask everything". The effect on the completion rate is dreadful. Beyond 15 questions, every added question drops completion by 1 to 2 points. At 25 questions, you typically lose 15-20 points compared with a tight questionnaire of 12-14 questions.
Worse still: the questions you add "for the DPO", "for the director of studies", "for the comms team" are rarely used in the final CGE report. They cost you responses on the questions that actually matter.
Antidote. Limit it to 12-15 mandatory CGE questions. Push secondary questions onto an optional second page ("Just 3 more minutes to help us get to know you better?"). For the detail of which questions to keep vs remove, see the CGE survey guide. For engineering schools also subject to CTI, be careful not to merge the two: see the 8 differences between CGE and CTI questionnaires.
Mistake 3 — Asking alumni to retype everything from scratch (no pre-filling)
The alumnus opens the form. They're asked for their cohort, their track, their last name, their first name. All information the school already has, but which they have to retype. Maximum friction, massive drop-off rate: according to our measurements, a form without pre-filling loses 20-30% of completion compared with the same pre-filled form.
Worse: this pre-filling is technically trivial. It's just a matter of generating a personalized link containing an identifier, which pre-loads the already-known data. Any serious survey platform does it by default.
Antidote. Pre-fill everything that's already known: identity, cohort, track, academic record. The alumnus only has to validate or correct. To measure the concrete impact, read our dedicated article on pre-filling and the response rate. Pre-filling turns a 10-minute form into a 2-3 minute one.
Mistake 4 — Sending reminders manually at random intervals
"We'll send a reminder next week if we have time". That's the sentence that sinks a campaign. Across 8 schools we support, those that send reminders manually run 1.3 reminder waves on average. Those that automate run 3 to 4 waves. The impact on the final rate is major: +15 to +25 points with structured reminders.
The problem isn't laziness: it's purely a mental-load effect. When you're juggling two campaigns (6-month + 30-month), alumni events, and membership-renewal reminders, you inevitably miss the optimal reminder windows.
Antidote. Schedule 3 to 4 waves from launch, on a fixed calendar: D+8 (reminder), D+18 (second reminder with a different hook), D+30 (SMS for non-openers), D+40 (targeted final reminder). All pre-written, all pre-scheduled. A platform like Terrilink Surveys lets you calibrate these waves once and for all.
Mistake 5 — Using an external sender address (consultancy, vendor)
Handing the sending over to an external consultancy looks professional. It's a disaster in terms of open rate. An email sent from "placement-study@consultancy-xyz.com" is 4 to 6 times more likely to land in spam or be ignored than an email sent from "alumni@yourschool.edu" or directly from the alumni director.
Based on our field observations, schools that switch from vendor sending to school sending gain +12 to +18 points of response rate, without changing anything else.
Antidote. Send from a school address, ideally a personal one (the alumni manager under their own name), with a human signature. If the consultancy needs to process the data afterwards, that's no problem: it receives the file, but it doesn't send the email. The sending channel stays with the school.
Mistake 6 — Ignoring the SMS channel
Alumni offices often resist SMS, for fear of being intrusive. That's a double mistake. First, the SMS open rate is ~95% against 30-45% for email. Second, alumni who don't open their emails aren't "absent" — they're simply saturated. A short SMS catches them back.
The quantified effect: on the n-1 and n-3 cohorts of schools we track, adding an SMS wave (never as a first touch, always as a reminder after 2 emails) brings +8 to +12 points of response rate. The cost: 4 to 8 cents per SMS, i.e. €30 to €60 for a cohort of 500.
Antidote. Schedule an SMS wave at D+25 or D+30, targeting only alumni who haven't answered 2 emails. Short format, direct link to the pre-filled form, school signature. No standalone SMS wave: it's the email-email-SMS sequence that delivers.
Mistake 7 — Forgetting transparency on data use
"We're asking you for this information for the CGE report". It's short, it's legitimate, but it's insufficient. A non-negligible share of alumni — especially those in transition (unemployment, career change, a break) — refuse to answer if they sense the data will feed rankings or be shared without control.
Based on our observations, 2 to 5% additional responses are recovered simply by spelling out: (1) who sees the identifying data, (2) what is published and in what form (always aggregated), (3) the right to rectification or deletion, (4) the CGE legal basis. This is also what the school's DPO expects.
Antidote. Add a short GDPR box (4-5 lines) to the form, a link to a dedicated privacy policy, and the statement "Your identifying data is never shared outside the school's alumni team. Only aggregated statistics are published in the CGE report." This transparency is also a best practice for the overall compliance of the campaign.
Fixing these 7 mistakes by moving to a dedicated tool
The 7 mistakes above can all be fixed "by hand". In practice, almost no school manages to fix them all together while staying on Excel + Google Forms. The calendar slips, reminders don't go out on time, pre-filling requires homemade macros, SMS assumes an external integration.
A dedicated tool for CGE surveys pre-fills, schedules the waves, integrates SMS, and exposes a real-time dashboard. On the first campaigns we support, the response rate typically climbs from 50% to 70% over two consecutive campaigns, with no extra workload for the team. To compare against benchmarks by school type, see our article on the CGE survey response rate by school type. To get started, the fastest route is to book a demo.