Nothing is wrong with it for now. It has been under Democratic rule and historically very stable. The issue is the first president ruled, then his son, who is now no longer ruling is out. He seems to be commenting and trying to almost influence the party he use to head up despite his term being over and no longer allowed to run. There is some tension because they are the same party, and people look at the region and instability from all sides and think it would/could be very easy for Botswana to go the wrong way. Especially if a major︀ Western power who has been know to play games in Africa, arm rebels, and back︁ coups etc. like Britain, USA, France, decide they want the new leader out.
I believe︂ Botswana is going through a new transition but it will likely turn out ok. It︃ is a small nation with just a few million people, and didn't have large number︄ of euro settlers that caused problems and complications in places like Mozambique, Zimbabwe, South Africa,︅ Kenya, North/West Africa, Congo, Rwanda etc.
The new president Masisi is very focused on expanding︆ the economy. However the opposition party has just successfully challenged in court his hotly contested︇ recent election. Masisi is hated by the old president khama because he has been cleaning︈ up corruption (aka firing his cronies who were stealing money) and using the country money︉ to do the right things. He is doing things Khama claimed couldn't be done. So︊ I would wait to see the outcome of the next election, because Masisi won 51%︋ of the vote but Khama is involved behind the scenes with opposition partywho only have︌ 31% of seats. Khama has a military backgground. While Botswana has never had a coup,︍ there was evidence a wealth south african family was involved in trying to do one︎ recently and if one is going to happen Khama would be the one to do️ it. I would wait 2-3 years before investing there until Masisi has firm control of things, because Khama is not going down quietly.
PS. while Masisi is the reasonable pro business party/candidate, the leader of the opposition coalition is promising to triple min wage, 100,000 public sector jobs (in a country of 2 million) and to increase pensions and presumably taxes.