They would lose that long term perspective if they were elected. The alternative is to have elected members, which brings you right back to the same problem.
In the US, our reps have two year terms. Senators have six year terms. The creators of the US Constitution at best could only hope for the Senate to be a "cooling saucer". Senators used to be appointed by state governors, which meant that they were also insulated from public election. The 17th Amendment made them elected by popular vote.

In theory, by having governor selected senators, there would be a delay between public sentiment and changes in the Senate. For example, if a governor won an election, they'd have to appoint the next open senate seat. Governors do not have long terms, so the Senator would remain in office, potentially, if a governor were to lose the next election. People didn't like that, introducing the 17th Amendment to make Senators more accountable. Consequently, they are now swayed by public opinion, which has largely resulted in the opposite of what was intended. Senators now rely on political contributions for their massive campaigns. And they have tended to weaken state rights and federalism as they no longer act as ambassadors for individual states.

In short, we aren't seeing much success with this way of populating the upper chamber. And in some states, you're seeing senators elected for decades who typically represent special interests more than their constituents. At least when they were appointed by governors, they had allegiance to their states.