The instinct behind the question is understandable. Stating a limitation feels like admitting a weakness, particularly when competing against businesses making broader claims. What actually happens is the reverse: specific commitments read as confidence, and vagueness reads as either inexperience or evasion. A business that says the first draft arrives on the fourteenth sounds more capable than one that says it will be in touch soon.
The distinction that resolves most of this is between what you cannot do and what you will do. I do not work weekends is a limitation. Work is delivered Monday to Thursday and you will always hear back within one business day is the same information stated as a commitment. Both describe identical availability, and only one of them sounds like a constraint.
Set expectations early, at the point of agreement rather than when something is about to go wrong. Expectations set in advance are terms. The same information delivered after a customer has formed a different assumption is an excuse, regardless of how reasonable it is, and it arrives at the moment they are least receptive.
Be specific with numbers and dates rather than relative terms. Soon, shortly, and as quickly as possible mean different things to different people and commit you to nothing while allowing the customer to imagine anything. A date is checkable, which feels riskier and is what makes it reassuring.
Build in the margin rather than promising your best case. A timeline that assumes nothing goes wrong will be missed, and a business that consistently misses its own dates trains customers to disbelieve everything else it says. Quoting a date you can hold comfortably and delivering earlier is a considerably better pattern than the reverse, and the customer experience of early delivery is disproportionately positive.
Explain the reason only where it helps the customer act, not to justify yourself. Telling somebody that a stage takes a week because it requires a response from a third party is useful, because it tells them the delay is not negotiable through you. Explaining your own workload is not useful and reads as a complaint.
Say what happens when something slips, before it does. A stated process for changes, delays, and problems means the eventual conversation is procedural rather than fraught. Customers accept that things go wrong. What they react to is discovering it late and having no idea what happens next.
Then hold to what you said, which is the part that actually builds the reputation. Expectations set well and then missed are worse than none, because you demonstrated precision and then showed it was decorative. A business that promises less and delivers exactly that is trusted more than one promising more and delivering most of it.
Write the important ones down rather than stating them in conversation, since spoken expectations become two different memories within a fortnight. A short confirmation message after any discussion about timing, scope, or cost costs two minutes and converts an understanding into a reference that either party can check.
Repeat them at the moments they become relevant rather than only at the start. An expectation set six weeks ago has faded, and restating the delivery date when the stage begins is not redundancy. It is what prevents the conversation where somebody believed something different and had no reason to check.
Check what your website and your proposal already promise, since those set expectations before you ever speak to somebody. A page implying immediate availability or same day turnaround creates a standard you then have to meet or explain, and it is a common source of expectations nobody consciously set.