There are so many misconceptions it would take a major article to cover all of them. Of course, a lot has to do with the lack of travel experience for the average US citizen.
Safety - In over 10 years we have never been mugged, robbed (except for phone in a crowd) or molested. Petty opportunity theft is rampant, if you lay your IPhone on the restaurant table and look away, it will be gone. The vast majority of robberies within a home is related usually to one of your employees so take some time to hire trustworthy employees. And even good employees go bad since the country is poor and household or farm employees just do not have much money so don't tempt them with the opportunity. If running a business, be sure to have good checks and balances and treat your employees fairly.
Political Stability - Could Nicaragua go bad like Honduras and Guatemala, sure but at this time it is a stable country with the last ten years showing good growth and many government programs to uplift the poor people. At this point in time I have more concerns on the political candidates in the USA.
Nicaragua is Hot - this is such a relative term since you can live by the ocean, in the mountains, in a metropolitan area, etc. Some places are warmer than other areas just like the USA. Most of us came here for the tropical weather. If you prefer having the four seasons (weather not the musical group) then you will not enjoy tropical countries.
The police are corrupt - Most of them are hardworking good policemen trying to make a living. Yes, there are a few bad ones and some supplement their income by pulling drivers over. But compared with the current police and incarceration issues in the states, we are not concerned with the police work here. We support our local police.
Realtors and Builders Will Rip You Off - A decade ago, there were a lot of corrupt realtors, developers and builders. Many, if not most, have been run out of town by now but always do your due diligence and talk to other expats.
OMG, There is a war going on in Nicaragua - we are so tired of hearing about the wars of the 70-80s. The first was the revolution of the people against the USA backed dictator Somoza. The second was a civil war caused by President Reagan and some politicians that used illegal means to install another puppet regime. Those days are long gone and the people hold no ill will against anyone from the states though they still hold a grudge against Reagan and the Bush presidents. Gun registration is very strict here and violence is not tolerated though most people here could not afford a gun.
I could go on but you get the picture. Nicaragua has a negative image which can only be changed by your visiting the country to see for yourself.