There is a pattern in IT vendor failure that almost nobody talks about: the breakup almost always happens between months 14 and 18.
Gartner pegs the number at roughly 60% of mid-market IT vendor relationships getting renegotiated or terminated within 18 months of signing. That is not a market problem. That is a structural problem with how the contracts are written and how the operational handoff happens.
After enough vendor selections you start to see why the cliff is so consistent. Three mechanics drive it.
Most multi-year MSP contracts have an auto-renewal clause with a 60-day notice window. Which means you have to give written notice in month 22 of a 24-month contract, but you do not know you are unhappy until month 16 or 17, when the operational drift becomes obvious. By the time you have decided to leave, you have already silently consented to another year.
This is the most preventable failure mode in vendor selection, and it is also the most common. Fixing it is a one-line contract redline at signing.
CFOs model the headline monthly cost into the budget. What they often do not model: 4-7% annual escalators tied to "labor index" or "inflation adjustment" clauses buried in the pricing exhibit. By month 14, the effective monthly spend is materially higher than the budgeted line item, and there is no opex slack left to absorb the surprise.
The renegotiation is not initiated by dissatisfaction. It is initiated by finance.
The team that pitched you the deal is not the team servicing you in month 16. Most MSPs run 25-35% annual staff turnover on service delivery (their churn, not yours), which means by month 14, essentially no one on your account was in the room when the relationship started. Institutional knowledge evaporates. Quality drops.
This one is harder to fix contractually, but you can underwrite against it during selection by demanding tenure stats for the named engineers, and revisiting those stats at the 6-month and 12-month marks.
The pattern is so predictable that any vendor relationship over 12 months deserves a structured health check. ITBluPrint does these for free on contracts older than 12 months. Request a health check