Google Ads, how exactly should placement areas be adjusted?

Recently a client asked me: We just started running Google Ads in 80 countries, but after a while, only 30 countries generated inquiries. Should we remove the remaining 50 countries?
The answer is "NO! It's not that simple and crude!"
Actually, when initially selecting target regions, we generally determine the final locations based on customs export data, industry data, historical conversion data, etc. After some time, if certain countries show no inquiries, we need to make adjustments by analyzing specific ad backend data.
First, for regions with high consumption share but no inquiries, consider pausing them temporarily.
Second, for regions with low consumption share but high CPC, try lowering bids first and make adjustments later.
Third, for regions with both low consumption and low CPC, maintain them and observe first.
Fourth, market demand is constantly changing. Monitor industry data and trends in real-time, assess market prospects, then decide whether to increase or decrease target regions while adjusting regional bids accordingly.
Fifth, utilize analytical tools like Google Trends. Enter product keywords like "construction steel" to check search popularity across regions for location adjustments.
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