sudo hostapd -dd /etc/hostapd/hostapd.conf
tells you if your config file is broken. Which helps.
Sample hostapd.conf for wpa-password protected access point:
ssid=myssid
interface=wlan0
driver=nl80211
hw_mode=g
channel=1
wpa=2
wpa_passphrase=mypass
wpa_key_mgmt=WPA-PSK
# makes the SSID visible and broadcasted
ignore_broadcast_ssid=0
PlanB 