What software should NOT be SaaS?

What types of business software should NOT be used on a SaaS model?
That’s something I’ve been thinking about lately as I read more and more cases of rising SaaS costs. The fact is, most businesses are paying more for their SaaS tools than they were last year. Same tools and users, just a bigger bill.
73% of SaaS companies raised prices in 2025, averaging 14.2% increases. SaaS inflation is running at roughly five times the general rate. CIOs now spend about 9% of their IT budget just absorbing price hikes on software they already have. According to Zylo’s 2025 SaaS Management Index, SaaS spending per employee hit $4,830 last year, up 21.9% from the year before.
For mid-market companies, per-employee spend jumped 40%. Gartner estimates 25% of all SaaS spend is wasted or underutilized. And 78% of CFOs say they’ve been blindsided by hidden fees or price hikes baked into their contracts.
The vendors aren’t subtle about this anymore. A few examples from the last two years:
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