I'm not entirely convinced.

Meaning

I'm hesitant to fully agree.

Examples

• John: 'This new marketing campaign will be a huge success.'<br>
• Alice: '<b>I'm not entirely convinced</b>; the target demographic might be too narrow.'
• John: '<b>I'm not entirely convinced</b>; we need more data to support that claim.'
• Alice: 'This strategy will definitely improve our profitability.'<br>