What constitutes "skipping steps" or "making assumptions" depends on context and perspective. We can't allocate conscious attention to all of reality – reality is too big, complex and varied.
To interact productively, people need some common ground – some shared knowledge and perspective – which specifies what sorts of assumptions are inappropriate to make. Shared culture is crucial for this.
Existing cultural defaults are adequate for working as a cashier. But our culture doesn't prepare people well for intellectual discussions. It's maybe pretty close to adequate for intellectual discussions, but some adjustments are needed.
As a starting point, for intellectual discussion, people should assume less than they normally do. Don't skip over some things you'd normally assume and then see which ones are or aren't an issue. But people are bad at assuming less, bad at judging which of their assumptions are riskier, and bad at updating their future behavior according to information gathered like this.