- Most S/4HANA delays come from decisions left open, not from technology.
- Measure what you really use before sizing the work. Much custom code can be retired.
- Choose the transition approach for business reasons and protect the time of process owners.
For most companies running SAP ECC, the question is no longer whether to move to S/4HANA but how, and how soon. SAP has set the end of mainstream maintenance for its Business Suite 7 releases at the end of 2027, with optional extended maintenance available to 2030 at additional cost. Programmes of this size take time to plan, fund and deliver, which makes the next year the real decision window.
Our experience supporting SAP in live manufacturing, retail and service operations is consistent: projects that slip rarely fail on technology. They fail on decisions that were never made early enough. Below are the five that matter most.
1. Know what you actually use
Every ECC system accumulates custom programs, reports, enhancements and interfaces over the years. Many of them no longer run. Migrating them all inflates cost, testing effort and risk.
- Measure real usage across at least one full business cycle, including month-end and year-end.
- Retire custom objects that have not run in the last twelve months.
- Replace custom logic with standard S/4HANA functions where they now exist.
- Keep a short, owned list of what must move, with a business reason for each item.
2. Clean the data you plan to keep
S/4HANA is stricter about master data than ECC. Customer and vendor records merge into business partners, and data quality issues surface quickly as failed loads and blocked postings during testing.
- Remove duplicate and inactive customers, suppliers and materials before migration starts.
- Clear or close old open items ahead of cut-over rather than after it.
- Assign a named business owner to each master data domain.
3. Choose the transition approach on purpose
There are three broad routes to S/4HANA. The right one depends on how well your current processes fit the business, how much history you need, and how much change the organisation can absorb at once.
| Approach | Best when | What you keep | Watch out for |
|---|---|---|---|
| New implementation | Processes no longer fit the business | Selected master data and open items | Larger change effort for users |
| System conversion | Processes are sound and well used | Configuration, history and custom code | Carrying old complexity forward |
| Selective transition | Some units fit, others need redesign | A chosen mix of data and processes | More planning and specialist tools |
If your processes no longer match how the business works, converting them faithfully to a new platform only makes the mismatch run faster.
Wakensys practice view
4. Line up the business, not only IT
Finance, procurement, production, sales and HR leaders decide how their processes will run in the new system. Their key users design, test and sign off the result. When their time is not protected in the plan, testing slips and go-live dates move.
5. Plan for the day after go-live
Hypercare, support tickets, training needs and enhancement requests all begin the morning after cut-over. Agree the support model, service levels and team before the project closes, so the system improves after launch instead of stalling.
A realistic sequence
Usage analysis, data quality review, approach decision and a costed roadmap.
Data cleansing, custom code clean-up, process ownership and team set-up.
Build, migrate, test with key users and cut over in planned waves.
Hypercare, support handover, training and the first improvement backlog.
- Which processes do we want to keep, and which do we want to change?
- Who owns each master data domain today?
- How much of our custom code still runs?
- Who will support the system after go-live, and to what service levels?
How Wakensys helps
We run short readiness assessments covering custom code, data quality, process ownership and the support model, followed by implementation, migration and application management. You get a realistic plan and budget before committing to a full programme.