diff --git a/testing-modules/testing/pom.xml b/testing-modules/testing/pom.xml
index 6f185d3b4c..c76045380b 100644
--- a/testing-modules/testing/pom.xml
+++ b/testing-modules/testing/pom.xml
@@ -161,7 +161,6 @@
                 <configuration>
                     <classes>
                         <param>com.baeldung.testing.assertj.custom.Person</param>
-                        <param>com.baeldung.testing.assertj.custom.Car</param>
                     </classes>
                 </configuration>
             </plugin>
diff --git a/testing-modules/testing/src/test/java/com/baeldung/testing/assertj/custom/AssertJCarAssertUnitTest.java b/testing-modules/testing/src/test/java/com/baeldung/testing/assertj/custom/AssertJCarAssertUnitTest.java
deleted file mode 100644
index d438cc42f6..0000000000
--- a/testing-modules/testing/src/test/java/com/baeldung/testing/assertj/custom/AssertJCarAssertUnitTest.java
+++ /dev/null
@@ -1,20 +0,0 @@
-package com.baeldung.testing.assertj.custom;
-
-import static com.baeldung.testing.assertj.custom.CarAssert.assertThat;
-
-import org.junit.Rule;
-import org.junit.Test;
-import org.junit.rules.ExpectedException;
-
-public class AssertJCarAssertUnitTest {
-    @Rule
-    public ExpectedException thrown = ExpectedException.none();
-
-    @Test
-    public void whenCarTypeDoesNotMatch_thenIncorrect() {
-        thrown.expect(AssertionError.class);
-        thrown.expectMessage("Expected type SUV but was Sedan");
-        Car car = new Car("Sedan");
-        assertThat(car).hasType("SUV");
-    }
-}
diff --git a/testing-modules/testing/src/test/java/com/baeldung/testing/assertj/custom/AssertJCustomAssertionsUnitTest.java b/testing-modules/testing/src/test/java/com/baeldung/testing/assertj/custom/AssertJCustomAssertionsUnitTest.java
index 8b800de3db..f9b5bad039 100644
--- a/testing-modules/testing/src/test/java/com/baeldung/testing/assertj/custom/AssertJCustomAssertionsUnitTest.java
+++ b/testing-modules/testing/src/test/java/com/baeldung/testing/assertj/custom/AssertJCustomAssertionsUnitTest.java
@@ -1,6 +1,7 @@
 package com.baeldung.testing.assertj.custom;
 
 import static com.baeldung.testing.assertj.custom.Assertions.assertThat;
+import static org.junit.Assert.fail;
 
 import org.junit.Rule;
 import org.junit.Test;
@@ -9,21 +10,35 @@ import org.junit.rules.ExpectedException;
 public class AssertJCustomAssertionsUnitTest {
     @Rule
     public ExpectedException thrown = ExpectedException.none();
-    
+
     @Test
-    public void whenPersonDoesNotHaveAMatchingNickname_thenIncorrect() {
-        thrown.expect(AssertionError.class);
-        thrown.expectMessage("Expected nickname John but did not have");
+    public void whenPersonNameMatches_thenCorrect() {
         Person person = new Person("John Doe", 20);
-        person.addNickname("Nick");
-        assertThat(person).hasNickname("John");
+        assertThat(person).hasFullName("John Doe");
     }
 
     @Test
-    public void whenCarIsUsed_thenCorrect() {
+    public void whenPersonAgeLessThanEighteen_thenNotAdult() {
         Person person = new Person("Jane Roe", 16);
-        Car car = new Car("SUV");
-        car.setOwner(person);
-        assertThat(car).isUsed();
+
+        try {
+            assertThat(person).isAdult();
+            fail();
+        } catch (AssertionError e) {
+            org.assertj.core.api.Assertions.assertThat(e).hasMessage("Expected adult but was juvenile");
+        }
+    }
+
+    @Test
+    public void whenPersonDoesNotHaveAMatchingNickname_thenIncorrect() {
+        Person person = new Person("John Doe", 20);
+        person.addNickname("Nick");
+
+        try {
+            assertThat(person).hasNickname("John");
+            fail();
+        } catch (AssertionError e) {
+            org.assertj.core.api.Assertions.assertThat(e).hasMessage("Expected nickname John but did not have");
+        }
     }
 }
diff --git a/testing-modules/testing/src/test/java/com/baeldung/testing/assertj/custom/AssertJPersonAssertUnitTest.java b/testing-modules/testing/src/test/java/com/baeldung/testing/assertj/custom/AssertJPersonAssertUnitTest.java
deleted file mode 100644
index ab421915af..0000000000
--- a/testing-modules/testing/src/test/java/com/baeldung/testing/assertj/custom/AssertJPersonAssertUnitTest.java
+++ /dev/null
@@ -1,26 +0,0 @@
-package com.baeldung.testing.assertj.custom;
-
-import static com.baeldung.testing.assertj.custom.PersonAssert.assertThat;
-
-import org.junit.Rule;
-import org.junit.Test;
-import org.junit.rules.ExpectedException;
-
-public class AssertJPersonAssertUnitTest {
-    @Rule
-    public ExpectedException thrown = ExpectedException.none();
-
-    @Test
-    public void whenPersonNameMatches_thenCorrect() {
-        Person person = new Person("John Doe", 20);
-        assertThat(person).hasFullName("John Doe");
-    }
-
-    @Test
-    public void whenPersonAgeLessThanEighteen_thenNotAdult() {
-        thrown.expect(AssertionError.class);
-        thrown.expectMessage("Expected adult but was juvenile");
-        Person person = new Person("Jane Roe", 16);
-        assertThat(person).isAdult();
-    }
-}
diff --git a/testing-modules/testing/src/test/java/com/baeldung/testing/assertj/custom/Assertions.java b/testing-modules/testing/src/test/java/com/baeldung/testing/assertj/custom/Assertions.java
index 5c72eb6d05..fcffb8fc6c 100644
--- a/testing-modules/testing/src/test/java/com/baeldung/testing/assertj/custom/Assertions.java
+++ b/testing-modules/testing/src/test/java/com/baeldung/testing/assertj/custom/Assertions.java
@@ -5,7 +5,5 @@ public class Assertions {
         return new PersonAssert(actual);
     }
 
-    public static CarAssert assertThat(Car actual) {
-        return new CarAssert(actual);
-    }
+    // static factory methods of other assertion classes
 }
diff --git a/testing-modules/testing/src/test/java/com/baeldung/testing/assertj/custom/CarAssert.java b/testing-modules/testing/src/test/java/com/baeldung/testing/assertj/custom/CarAssert.java
deleted file mode 100644
index 413c2d3e12..0000000000
--- a/testing-modules/testing/src/test/java/com/baeldung/testing/assertj/custom/CarAssert.java
+++ /dev/null
@@ -1,30 +0,0 @@
-package com.baeldung.testing.assertj.custom;
-
-import org.assertj.core.api.AbstractAssert;
-
-public class CarAssert extends AbstractAssert<CarAssert, Car> {
-
-    public CarAssert(Car actual) {
-        super(actual, CarAssert.class);
-    }
-
-    public static CarAssert assertThat(Car actual) {
-        return new CarAssert(actual);
-    }
-
-    public CarAssert hasType(String type) {
-        isNotNull();
-        if (!actual.getType().equals(type)) {
-            failWithMessage("Expected type %s but was %s", type, actual.getType());
-        }
-        return this;
-    }
-
-    public CarAssert isUsed() {
-        isNotNull();
-        if (actual.getOwner() == null) {
-            failWithMessage("Expected old but was new");
-        }
-        return this;
-    }
-}