"Responsive" is about the bid; "responsible" is about the company.
Common reasons a bid is non-responsive
- Missing signature or notarization where required.
- Addenda not acknowledged.
- Missing bid bond or required affidavits.
- Prices left blank or in the wrong format.
- Conditions added that change the county's terms ("price valid if…").
A county can sometimes waive minor irregularities that don't affect price or fairness, but it isn't required to. Don't count on it.
Responsibility looks at capacity: experience, finances, licenses, equipment, past performance and insurance. Some counties ask for this up front (for example, Indiana's public works bidders submit a financial statement and statement of experience on state forms); others check only the apparent low bidder.