Why may stealth scans attract more attention than simple connect scans?

Good day, I'm reading a book about Information Security and I am faced with the question "Why may stealth scans attract more attention than simple connect scans ?" (nmap). My answer will be something like: Because stealth scans can be detected and logged by some firewalls as "not established connections". Is it ok? If not can you please add your comments why they can attract more attention..